I decided to go with the Sansa e260.
I was thinking about something like
COWON A3 Personal Video Player or
Archos 605 WiFi. I think these devices need to get better b4 I buy one.
Archos: Won't play MKV files.
COWON: No touch screen control.
Yeah, I'm awfully picky.
The e260 got decent reviews and some recommendations here. I'm sure I'll be happy with it. I hear the video on this thing is terrible. You need to transcode everything to ultra-small yet still the same file size quicktime, and as we all know quicktime sucks.
Also, my NDS is a media player thanks to the almighty
R4. Turns your DS into a media player! This is what I use now. It'd be better to have a dedicated device, as storage space is higher, interface is better, and battery life is longer.