O Death, where is thy Sting? (or Bono)
My 60GB 5th generation iPod was working just fine – for years – but the other day it joined the choir invisible, shuffled off its mortal coil, went to meet its maker. This iPod appears to be an ex-iPod: it's bleeding' demised.
Personally, i'd take the whole thing to bits and put it together again and plug it in (works for cars[maybe without the plug it in bit but you get my point]) Add a new battery first (again works for cars and iPods often) then your iPod should tell you what its problem is by its error code, or maybe its just old and fed up with its software and wants the funky new (3.1 lol) software update, works for me a lot of the time.