Just piping in with what seems to have worked for me...it was helpful for me to read other's suggestions with different wording, so hopefully this adds to the discussion.
For me, having a USB and a wall adapter seemed to do the trick.
1. Plug flailing iPod into your USB port. You should see the Apple screen, followed by the frowny iPod, followed by the infamous "Please Wait. Very Low Battery" message. I always got this sequence consistently when plugged into the PC; this was not so when initially plugged into the wall adapater.
2. Leave it at the "Please Wait. Very Low Battery" message screen for a bit, maybe 10-15 seconds. I did not find a need to repeatedly repeat steps 1 and 2 as others have suggested.
3. Unplug your iPod.
4. Press Select and Play, and hold them down for dear life. This is what I didn't really get until recently; I was always pressing a button first to get to the Apple screen, and THEN pressing and holding Select and Play. I consistently got it into disk mode by holding Select and Play from a completely blank screen at this step.
5. You should notice that the Apple logo lingers for quite awhile while the iPod makes buzzing sounds. When "OK to disconnect" appears, plug it into your wall adapter. I found that if you plug it into your USB port at this point, "OK to disconnect" will change to "Do not disconnect", and that your iPod will revert to the cycle cited in step 1. I'm currently charging with my wall adapter, and have been doing so for about 10 minutes.
Not too sure where I'll go from here, but it definitely appears to be progress. Will keep you posted.