My iPod likes to magically turn itself on. As in, I will take it out of my bag, pause it, walk up to my work, take it out of my bag again, see that it has turned itself back on, and then pause it again.
Ten minutes later, I check it and IT IS STILL PLAYING MUSIC.
This, NOT THROUGH LACKADAISICAL CHARGING HABITS I SAY, is why I never have any batteries left in my iPod.