A few months ago my 40gig 3g ipod died on me. The hard drive failed, and I no longer could put music on or listen to it. My buddy, who has a 3g 10 gig, had problems with his. Starting a year ago he could not use any of the touch buttons on the face. The buttons would not respond. Sometimes he could press play and it would play, but the scroll wheel did not work, so it was almost useless.
Anyways, he got himself a video ipod, and received another 20 gig from his family, so he gave me his 10 gig. So I took apart both my old 40 gig and his 10 gig, and using working parts from both, I pieced together a working 10 gig ipod! It was much easier than I expected, and now works great. I just hope it keeps working!