The hard drive in a friend's 4th generation iPod 40GB died awhile back (the 2nd drive to do so) and I'm looking to resurrect the iPod. I've read that people have successfully installed a 60GB Toshiba hard drive in this model, but I was wondering if there's any reason a smaller hard drive wouldn't work. I can get a 20GB 1.8" Toshiba drive for about $25, which is not to much to spend if the drive fails. Has anyone tried a non-Toshiba drive or know why one such would or wouldn't work? What about solid state drives? I think I can find a 32GB SSD with the correct interface for around $100, and its reliability might make the price worth it. We don't want to invest too heavily in a mechanical HD in case the replacement drive fails, and my friend has soured on Apple as a result of two failed drives within 1.5 years (he doesn't want to give them more money for a new iPod).