1. The hashtag #eastwooding went viral on Twitter after Clint Eastwood's guest appearance at the Republican National Convention, where his speech focusing on an empty chair meant to represent Barack Obama baffled many. Obama's team eventually tweeted a tongue-in-cheek photo of the President sitting in a chair with his back to the camera, captioned: "This seat's taken."
2. A YouTube video managed to poke fun at the otherwise gaffe-free Obama. The spoof lip-read of the first debate mocks the President's lacklustre performance. At one point, Obama appears to be dozing on his feet. "Yep, er, he's asleep" a wide-eyed Mitt Romney quips.
3. Mitt Romney's "Big Bird" comment at the first debate featured widely on Twitter, with several parody accounts created. "I like PBS (US public TV network). I like Big Bird," Romney said, but nevertheless pledged to cut support for public television. The Twittersphere exploded. "Obama killed bin Laden. Romney would put a hit on Big Bird," @EliClifton joked.
Romney even managed to anger otherwise bored children watching the debate. "What? ... I vote for Obama anyway," one kid says in a widely viewed YouTube video.
4. Hot on the success of South Korea's Gangnam Style song, comedy website CollegeHumor put out Mitt Romney Style. A Romney look-a-like prances around stables and golf courses to the rhythm of the original song. "Affluence, extravagance, that's Mitt," the lyrics say at one point, as "Romney" laughs at a waiter who has a "47 per cent" sign on his back - a reference to his comment writing off 47 per cent of the US electorate.
5. The second debate also provided fodder for online comics as Romney, asked about unequal pay, responded that as Massachusetts governor, he went out of his way to add women to his staff. "I went to a number of women's groups and said: 'Can you help us find folks,' and they brought us whole binders full of women," he said. The Twittersphere lit up, and a satirical account on Tumblr - the blogging platform - was set up, featuring photos of women wearing custom-made binders: bindersfullofwomen.tumblr.com.
6. When Obama ironically mentioned during the third debate that the army had fewer horses and bayonets than before, the internet went crazy. One Tumblr page spawned countless parody photos: horsesandbayonets.tumblr.com. A shot of Obama leaning over to speak to Joe Biden features the caption: "Iran might get a nuke. Do we have enough horses and bayonets?"
7. Saying the middle class had been buried over the last four years, confusing Iowa with Ohio ... Vice-President Biden has attracted a lot of attention. YouTube is full of videos putting his gaffes - "Bidenism" - all together.
8. Paul Ryan spawned a few chuckles when Time published photos of Romney's running mate pumping weights with a red cap on back-to-front. The shots spurred a rash of animated pictures, funny blog posts and a fake Twitter account called @PaulRyansBicep.
9. Jim Lehrer, a respected journalist, may have regretted his decision to moderate the first presidential debate. By the time it was over, the Twittersphere was busy poking fun at the 78-year-old - who was widely regarded as not being tough enough - and an account called @SilentJimLehrer had sprung up, garnering thousands of followers.
10. Lastly, the Democratic National Committee set up a website mocking Romney's tax plans. "For a detailed explanation of how the Romney-Ryan tax plan is able to cut taxes by US$5 trillion without exploding the deficit or requiring tax hikes on the middle class, simply click the button below," it says. But the button moves to the side every time the mouse gets near: romneytaxplan.com.