Samsung Slider D807
I got this one about 6 months ago and am very happy with it. Records video and audio. Plays mp3's as well. I haven't tested out it's mp3 playing abilities but I know it does it. I paid about $125 with a 2 year contract 6 months ago. I think you can almost get one free now also.
The Samsung Blackjack looks pretty sweet also, but it's gotten mixed reviews.