Like virtually no one else in the country, I stayed up to watch the final US presidential debate the other night, which started at the user-friendly time of 2am and lasted 350 hours, if you count all the post-match analysis. All the rolling news channels were covering it live, of course, so my choice of network was largely based on aesthetics. Sky News had the colour turned up to cartoon levels, so that was out. The BBC had a more sober palette, and was showing it in widescreen, but there weren't enough distracting tickers and graphics to maintain my attention - I know they're bad, but I just can't help myself - so before long I started channel-surfing. The moment I alighted on CNN, I knew I was going to stay there. Why? Because they had an animated graph.

It looked like a heart monitor. For a moment, I thought it was displaying the opponents' pulses. Or maybe it was hooked up to a pad in their seats, and was scrupulously monitoring the amount of arse sweat they'd generate if a tricky question reared its head. But no. Instead it was supposed to be a visual representation of the ever-shifting mind-set of a group of uncommitted Ohio voters.

Rather than shoving electrodes into said voters' brains, so they looked like miserable cats in an anti-vivisection poster, CNN had taken the humane route and given them some sort of approval-rating widget. So if you were holding one, and Obama said something you didn't like, you turned the dial down, and if McCain said something you did like, you turned it up. And vice versa. There was one line for women and another for men, so you could see how the different sexes had different reactions. Sadly, that was the full extent of demographic separation. They could've broken it down a little further. It would've been fascinating to see how, say, overweight ginger-haired postmen felt about the possibility of a new free trade agreement with Colombia, but the lazy bastards at CNN couldn't be arsed to tell us.

This shocking oversight aside, watching the wobbly line snake up and down as the candidates spoke was mesmerising. So mesmerising you couldn't really hear what they were saying. In fact, it turned the debate into a video game - like SingStar, the PlayStation karaoke thing where you get drunk and try to belt your way through Girls Just Wanna Have Fun without hitting too many bum notes.

When the delicate subject of abortion came up, the line became yet more fiddly, and turned into one of those infuriating puzzles where you have to move a metal loop along a twisty-turny electrified wire without touching the sides.

Since it's impossible not to root for one candidate or another, this meant that you found yourself egging your favourite on in craven and bizarre ways. "Shit, the line's dropping - quick, make a rash promise to the American people! Say you'll eliminate taxes! Claim to be Christ! Offer free hand-jobs! Anything!"

At one point I found myself thinking it'd be useful if people had those approval-monitor graphs on their faces in real life, so when you were talking to them at parties you could tell, at a glance, just how interested or bored they were. Then I remembered that's what basic facial expressions are for. Nature always gets there first.

Speaking of facial expressions, during the eight or nine nanoseconds I wasn't focused intently on the animated line, the lingering reaction shots provided much entertainment. The screen was split in two so you could see their faces while the other was talking. Obama smiled a lot, so much in fact that he started resembling a reality show contestant watching a compilation of his "best bits". McCain's face didn't know quite what to do with itself. It kept trying to look furious. Then you'd see him remember that looking furious doesn't play well, so he'd arrange his face into a tight, eerie grin, while appearing to grow increasingly furious with himself for failing to hide his earlier fury, thereby creating an unfortunate anger-based feedback loop. He should've worn a mask. Is the world ready for a masked president? Hell, yeah. How about one in a Sarah Palin mask? Or Chico Marx? Or Jason Voorhees from Friday the 13th? That'd really have thrown Obama off his stride, and given the networks something else to debate ad nauseam, thereby putting McCain back at the top of the news agenda. Is this a new maverick strategy, or a mental breakdown? The pundits would be at it for hours.

Despite the visual distractions, a few words and noises did register in my brain. Obama's voice is so soothing, I kept thinking he was about to start advertising coffee. "I want to say to the American people: this is the finest, mellowest blend your money can buy." McCain, meanwhile, was narrating a children's story about Joe the Plumber. Maybe it's a back-up plan: if he doesn't win the presidency, he's going to launch a stop-motion animation series on Nickelodeon. There's probably a warehouse full of Joe the Plumber action figures out there somewhere in the Arizona desert just waiting for the say-so.

I kept waiting for Obama to counter McCain's talk of Joe the Plumber by bringing up Boris the Spider or Dennis the Menace or something, but no. He started addressing Joe too. Before long they were both at it, appealing to Joe straight down the lens, which meant I had to keep looking behind me in case he was standing there, fixing a pipe.

Then it was over and I went to bed. At least I think I did. Perhaps it was all a dream. Certainly felt that way. An election in Narnia. And they all lived happily ever after. The end.

• This week Charlie struggled to understand the interface on his new phone: "It's like a cross between Windows and a sarcastic cartoon about Windows, with the added disadvantage that you have to try to operate it with your stubby little thumbs."