I wouldn't get a classic since it has a hard drive in it. Stick with a flash based memory model. You could always get an old school ipod mini on ebay for 20.00 and throw in a 16gb compactflash card for 40.00
It cost me 60 bucks and I have a converted mini with 16 gigs of space. Perfect for the mountain cuz it lasts all day and there is little to break on that thing.