This is an awesome site: tap your spacebar in the rhythm of a song and it tires to guess. It guessed the Final Countdown intro and There's No Limit! correctly with me...
http://www.songtapper.com/s/tappingmain.bin
Awwww. I tried six different songs, and apparently, they were ALL "Smooth Criminal" by Michael Jackson...
Funnily enough, I just tried "The Joker" bassline and it thought it was smooth criminal, too. I can see why though...
It missed my first one (No Scrubs, by TLC), despite having the song in it's database, but it got my second one (This Love, by Maroon 5), despite me thinking I'd tapped it wrong.