One bad thing that could happen.
You are on a train day journey, you don't have company and no books too.
You have started the trip with a fully charged up IPod and then doooom.
The IPod gets hung, press buttons in a any sequence it doesn't budge one little bit.
When such a thing happens, you need to press together the Menu button (top) and the
Center button (Dial) and keep pressing them for sometime till the Apple logo comes up.
Then the system is supposed to have rebooted and things will start from square one.
I did not know this then and ended up spending a 6 hours boring train journey en route to Chennai from Bangalore.
Sources from Google.