If you’re having a hard time figuring out which $20 to $40 case makes sense for your iPod nano, take a look at business card cases as a nano case until something custom made strikes your fancy (and wallet).
I found this Swiss Army leather (or at least leather-like) case that fits the nano perfectly at a local Office Depot store for $10. I stuck a few business cards in the pocket in front of the pocket holding the nano to provide a bit of extra stiffening and screen protection. It has been working well for me for the past couple of weeks.
Any other inexpensive nano tips?