What's on your workout playlist?

OK... congratulate me; I joined the (very nice, reasonably priced) gym at my workplace.
Now... I spent approximately 40 minutes on the treadmill and elliptal trainer today, flipping from album to album (I have a few albums I regularly listen to while running outside, and I can get around the lake in about an album... but it's just a different vibe).

I got some really great feedback on suggestions for songs to add to my deadlines playlist; so I'm putting the call out again.

What do you all work out to? it's gotta be something with a great beat -- something a little angry -- something definitely fast (motivate me to run that 10-minute mile). I have an appointment to learn the machines and start strength training midweek next week -- do you listen to anything different for that?