Never been the biggest fan of mash-ups (have a couple favorites, but they have to be done perfectly) but this one is kind of cool.  Not my favorite song, but it uses all the top songs from 2011.  

Can't even hate on it too much.  Not that I like any of the songs on it, but because DJ Earworm has an impressive finess for mixing these things up.  So there you go, jam out and celebrate all the annoying songs that clogged your radio waves for the past 12 months.