MP3 Player?

I'm considering getting an MP3 player for commuting (no cd player in the car; I plan to use a cassette adapter) and walking the dog (Charisse, our six-month-old Old English Mastiff).
One co-worker suggested an I-pod. I would have to get the PC version (99-cent songs sounds really good). Initial outlay is a little steep right now though.
I'd like the option to rip cd's to the player itself and 2 to 3 hours of music is plenty. Expandability would be nice also.
Something around $100 is about all I can do right now.
Does anyone have any suggestions?

[This message has been edited by CBWills (edited October 21, 2003).]

I use an "edigital MXP 100" for running and other exercise. It uses Compact Flash cards for storage and has built in lithium battery so recharging is no problem. I use it all week at the gym, about eight hours total, and the charge has never run down on me. I have had it for about a year now with no problems.

gwhunran,
I bought a MXP100 on ebay about two weeks ago.
This is a great player, although the program to load it does leave a little bit to be desired.

Thanks for the suggestion.