Have you any other machine you can plug it into?...even a Windows based one? If none of your Macs are recognizing it.
If so and it comes up in iTunes...do a complete reset.
Does the iPod, as far as it can without iTunes, work?
Have you tried a soft reset? (Hold down menu and select for about 20-ish seconds?) The Apple logo should emerge.
Has this iPod worked before in the past?
Are you running all Intel-based Macs running the first version of the 10.4.10 update? (I know this caused problems with USB drives and other devices, I had this personally, though not with an iPod, so I'm not sure if it affects iPods).
1. I've tried Windows XP, PPC Macs and Intel Macs - not coming up on any of them - will charge though.
2. iPod works fine both video and audio-wise
3. iPod has worked flawlessly in the past - never had a need to reset or ever hard-restart it.
4. Have tried 3 different USB cables
I'm going to try to let the battery drain down all the way and then try plugging it in. If it still doesn't mount where should I get it repaired? Apple, iPodResQ, etc?