Thought I'd share what worked for me. Ipod Classic 160gb (6G) was dead (or so I thought) and I was about to call Apple Support or start opening up the damn thing.

Cause:
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Suppose it was because I've gone over the 4gb (not sure about this) limit with filesizes.
Pretty sure that I had "enable disk usage" on, but I did paste about 15gb of non mp3s in the notes folder using Explorer. (Some Avi's, rar files, excel files, installers from
portableapps.com etc)

When I unplugged, the ipod was dead.

Note: throughout I will be referring to resetting the ipod or the 6G (5G too, methinks), its:

Reset:
Hold [on] - few seconds
Middle & Top buttons - about 10 seconds
Apple Logo Appears

Enter Disk Mode:
Middle and center buttons for a few seconds after abovementioned apple logo appears

See http://www.command-tab.com/2006/03/30/hidden-ipod-commands/ for more details if you're unsure.

Failed Attempt #38484
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Left it for 24 hours
Plugged it into the usb port
Saw the "Charging, please wait..." image
Tried resetting, but it went back the the Charging screen
Left it to charge
After about 30 minutes, it was dead again (even while plugged in)

Solution that worked:
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Left it (unplugged) for a few hours
Plugged it into the usb port
The "Charging, please wait" screen appeared
Tried resetting (after a few seconds of blank screen it defaulted to "Charging, please wait" again)
Kept on "resetting" to the CPW screen while logging into Windows (notebook was asleep at the time, I didn't expect success)
Once logged in (with Windows Explorer open & waiting), I reset the Ipod again - and this time it worked.
Seems like the thing needed a little more power or charge time.

The apple logo appeared. Then, immediately I switched to Disk Mode, then used Explorer to remove those damn files
Did another reset

Ipod = healthy
All my songs are fine, etc.

Hope this works for other people too.

/me happy
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