20:25 - Well, I've got a car waiting for me, so I'd better make a dash for the exit. The verdict here is this was a score-draw - which helps both these minor teams' chances of working their way up the table.
20:20 - I've just been speaking to some Dutch journalists to get an international take on the debate. They were impressed by Clegg because he speaks Dutch - and four other languages, of course. It meant they were biased. But they did think that voters might see Clegg in a refreshing new light. "Campaigning Clegg is better than the 'sad Clegg' of coalition," was their thinking. Not that they thought Farage did badly, either. He's going to win more votes than Clegg, they suggested.
20:15 - "It's been a great night for British democracy," says Paul Flynn, Ukip's spinner-in-chief. There is a bizarre sort of truce here - they disagree so clearly we're not getting the usual 'battle for power' tensions in the spin room that you would expect from after the televised debates.
20:10 - Having fought my way through the hordes of TV cameras, I come across Nick Clegg's special adviser surrounded by a huddle of journalists. He's very positive, not so much about who won the debate, but about the fact that he thinks the Lib Dems will ultimately win over voters as a result of this. The Tories and Labour, by contrast, didn't have the "courage" to participate and so are only worthy of yah-boo-sucks, etc.
20:07 - I've just spoken to Peter Bone, who tells me he accepts it would have been handy for the Tories if Cameron had been involved. "It would have been good to be there to tell them we're the only ones who can offer an answer," he says. He also queries the seven per cent figure which Clegg cited - he's going to be checking that in the House of Commons library tomorrow morning...
20:02 - Well, my snap verdict is that Clegg got the better in terms of substance, but that is was probably a draw overall on style. Time to find out what everyone in the spin room has to say about it... I'll post more sporadic updates on here over the next half-hour, after which I'm jumping in a car and going to talk to Al-Jazeera...
20:01 - Farage's conclusion is less polished. But he's trying hard. "Nick represents a tired status quo... I believe the best people to govern Britain are the British people themselves." He also finishes with an appeal for votes. And it's over. Thank the lord.
20:00 - Clegg's final message is utterly pre-scripted. "I want us to be Great Britain, not little England, and if you feel the same now is the time to make your voice heard." He suggests that people who haven't voted Lib Dem before might just want to "give us your support". A direct appeal for votes to finish, then. Nice.
19:59 - The final question is about Ukraine, giving Clegg a great chance to make the point that many countries are really, really keen to join Europe - not leave it. It means Farage will get the last word, though... and he uses it to take the opportunity to be statesmanlike. While using the phrase "geed up". He says the European Union has "blood on its hands in the Ukraine".
19:56 - And in the dying moments of the debate, Farage is being attacked for paying his wife. "I very much doubt anyone in British politics has worked the hours and had as little fun as me." The spin room erupts in laughter.
19:55 - Farage says 75% of laws which sit on the statute book are generated in Brussels. When pressed, he reveals that that stat is just the "Ukip estimate". Clegg says the House of Commons thinks the real number is seven per cent.
19:54 - "Oh dear, oh dear," Farage sighs. A nice bit of political punctuation, there, which allows him to re-establish control. "We believe in the Anglo-Saxon rule of law," Farage says. Which is both accurate and has xenophobic overtones.
19:52 - One thing is clear: Clegg clearly wins on the name-checking-the-questioner front. He isn't even scribbling down their names to remember them, either. Farage hasn't really bothered.
19:51 - Now we're talking about gay marriage, that fundamentally important European issue. Er... Clegg talks about it being a "wonderful step forward" and gets a round of applause from nowhere. Farage looks a bit confused.
19:50 - And now it's Clegg who's getting riled. He shakes his head, gets stuck like a broken record trying to interrupt Farage, and ends up being shut up by Ferrari. He smiles ruefully, having allowed himself to get a bit carried away there. "Why is it that Ukip dogma is so strong now you won't help British tourists who get stuck on the wrong side of the law?" But it's Farage's response that gets the round of applause.
19:48 - Farage, who has been struggling on this, says the European arrest warrant is "totally unnecessary". He's not coming up with so many figures or stats here, though. Without some random numbers to come up with, the Ukip case is weakened. "This is fantasy, this is complete fantasy," Clegg says.
19:45 - Clegg tries a new style - "do you remember, Clive?" - providing two examples of extraditions which allowed Britain to get criminals "to face British justice". Clive seems nonplussed. Ferrari comes back with Abu Qatada. "It has nothing to do with the European Union," Clegg complains. Well, true, but it IS the European convention on human rights...
19:44 - "There are a lot of things we can learn from Europe," Farage says. "The food's getting better here, and that's great." That joke goes down like a lead balloon. Farage chuckles to a silent room. Agonising.
19:40 - Another whip-out from Ferrari of a Ukip leaflet, but I'm not sure this one is anywhere near as damaging as Clegg's. The total cost of Britain's membership of the EU is £50 million a day. "That's a low figure - the true cost is many times that," Farage replies. Clegg says the claim is "simply not true". Classic Lib Dem campaigning here - undermining the opposition's figures.
19:38 - Clegg drops a bombshell: he reveals he was involved in trade negotiations himself! Sacre bleu! Clegg makes a "by the way" point that he was elected to the European parliament on the same day as Farage. "I left the European parliament, he remains a euro politician." Farage grins inanely.
19:35 - Clegg's response is to look beyond Europe, asking whether Britain will have the same "clout" outside the EU. Farage replies: "You don't really understand the world of commerce and trade." More of the same, it seems.
19:34 - Farage attacks Clegg - and then "all of you, you all do it", he says, attacking that three million figure on overdrive. "The United Kingdom is now the eurozone's biggest export market in the world," Farage says. "Trade is not something created by politicians and bureaucrats - it's created by consumers who make a decision." Farage gets one over on Clegg by boasting about spending "20 years in the private sector". "We actually hold the whip hand," Farage insists.
19:32 - We're back to the old jobs debate now. Clegg says three million jobs are linked to the eU. In th espin room, the LBC logo is wobbling around like crazy. The journalists all seem thoroughly engrossed, though.
19:30 - The longer this goes on, the more absorbing it gets - and the stronger the sense grows that Cameron and Miliband are being damaged by this event. This is undoubtedly win-win for these two. Both sides will get their votes out more strongly as a result. What about the Tories? What about Labour? Right now, who cares about them?
19:27 - Clegg's "gang", Farage says - "you know, you and all your corporates". Er, what pesky liberal corporates are they exactly?
19:26 - Drawbridge bingo: That's the second time the deputy prime minister has used the 'pulling up the drawbridge' phrase this time around. Does that mean anything in bingo, actually?
19:24 - A bit scrappy, there, from both in reality. The camera pans away to reveal big television screens on the floor with a 60-second counter. The sort of thing which both men have to pay attention to, while not indicating to anyone they're doing so. Presumably when you see them staring thoughtfully at the floor, that's what they're up to...
19:22 - Farage's claim that Clegg is speaking for all three mainstream parties is being reinforced by the Lib Dem leader, who's defending the coalition's policy of making it harder for arrivals from the EU to claim benefits.
19:19 - Now things are starting to heat up. Farage, who was obviously riled, is battering away at Clegg like a crazed euro-badger. This is bad for Farage: he shouldn't let himself get too worked up. He might even start sweating.
19:17 - What Farage is saying, Clegg says, is just "not true". Clegg whips out a Ukip leaflet warning that 29 million Romanians and Bulgaria will come to Britain. "There aren't even 29 million Romanians and Bulgarians living in Romania and Bulgaria!" Clegg says. That's a point scored if ever I saw one...
19:16 - Question number two is about freedom of movement within the EU. Clegg says pulling up the drawbridge would "destroy jobs for everybody in this country". Farage, who has a tricky test with this one, moans about the "total open door" to Europe. "No," Clegg says repeatedly, to which Farage starts moaning about "weasel words". The audience claps appreciatively.
19:14 - When given the chance to moan about David Cameron and Ed Miliband refusing to play ball, Farage and Clegg quickly start digging in. Ferrari then asks an important question: will the existence of Ukip stop the best chance for eurosceptics of getting a referendum - ie, a Tory election victory? Farage's reply is that only one in three voters are from Conservative - the rest come from old Labour or people voting who hadn't bothered before.
19:11 - This opening exchange is very telling. When they begin exchanges between the two of them, the content of what they're saying is actually quite useful. Farage's attempt to paint Clegg as speaking not just for the Lib Dems but also for all the mainstream parties seems like a decent early point. And then Ferrari pulls out a humdinger of a 2008 Lib Dem poster of Clegg calling for a referendum. I'm not sure many liberals will be happy with that, so early on in proceedings...
19:07 - The first question is about asking for a referendum. And I don't know whether it's the ridiculously loud volume of the PA system in the spin room, but it sounds to me like he's shouting his head off...
19:05 - Farage looks very top-button-done-up compared to Clegg, who seems like an old hand. But he's doing the whole gazing-at-voters thing very well, and gets off to a solid start by changing the question. What would you vote for if the debate was about joining Europe?
19:05 - Clegg's message is: "for the sake of jobs, for the sake of our clout in the world, for the sake of Britain". Belated applause from the studio audience there.
19:04 - After Farage wins the toss and puts Clegg into bat, Clegg kicks off by doing that whole talking into the camera thing that, let's face it, worked very well in 2010.
19:03 - "You've waited decades for this debate," says Ferrari, kicking things off. Journalists in the spin room laugh sarcastically.
18:59 - The sound of Nick Ferrari warming his audience up with some practice cheering drifts over the spin room. It is both ethereal and annoying... nearly time to go, now.
18:56 - We're nearly ready to go. I have this from one of Nick Clegg's aides: "He's looking forward to it." Which, as the aides points out, is not surprising because he was the guy who challenged Farage. More red-hot news as it happens. Although, thankfully, we're just about to start...
18:52 - Bone says it's going to be "interesting". Which is, as it happens, not a very interesting thing to say.
18:50 - Various luminaries are in the spin room; Tory Clegg-hater Peter Bone is being interviewed to my right by the Beeb right now, and way at the back Danny Alexander is working the room too. Sort of.
18:37 - But there is something about this which is different. The glamour of a live debate, with its confrontational buildup and the thoroughly conscious attempt to evoke the atmosphere of a heavyweight boxing match, isn't your everyday political event. From 7 until 8 (what, a whole hour?) the leaders of Ukip (crazily anti-Europe) and the Liberal Democrats (crazily pro-Europe) will go at each other hammer and tongs in a bid to mutually shore up their support. Both will win, because both will be mobilised. I can't wait.
18:36 - If you're following Sky News' thoroughly overexcited coverage of the debate - a clever and astute move which virtually everyone in the Westminster establishment secretly welcomes - you'll already be in a frenzy of anticipation at the thought of two politicians arguing with each other. It's extraordinary, really, that this is newsworthy. You can watch tedious exchanges between people who disagree with each other every day in the Commons chamber, after all...
18:35 - Good evening, one and all. The wi-fi password has been entered. The long-suffering colleagues have been brutally shoved aside to make room for a late entry into the spin room. Egad, what's this? It's politics.co.uk's live coverage of the Clegg v Farage farrago...