It may come as no surprise that I have a little stash of MP3's awaiting use
I had Andreas Johnson's "Glorious" earmarked, but another member used it and I applaud his fine taste! This was the BBC's music of choice for the BT Global Challenge 2000/1 so it has great pedigree.
I have a bit of a rap thing going on at the moment and would love to use these two:
Enimem - Lose Yourself
Busta Rhymes Ft. Linkin Park - We Made It
But what about the "Cars" Soundtrack - Sheryl Crow's Real Gone - a great song!
Or Moby - Extreme Ways (Bournes Ultimatum).
And I think Justin Timberlake's What Goes Around...Comes Around might work well.