The MP3 player takes on a whole new dimension--literally--with the Walletex Wallet MP3 player. It measures a measly 2mm/0.091 inch thin--thinner than a pair of credit cards and slim and tough enough to store in a credit card wallet slot.
On one side of the player are the usual transport keys that require a forceful push, which means the thing won't accidentally start playing when it's in your wallet and you're sitting on it.
Sticking out from one end is a unique all-purpose sliver USB jack that's the same thickness as the rest of the unit. This jack can be plugged into a standard USB plug for syncing and battery charging (2 hours to a full 5-hour play charge) and is also the headphone jack; the lanyard earbuds have a plug that fits around the sliver.
The top can be imprinted with any logos or graphics, so even if you can't find one in a store, there's a good chance they will be a popular promotional item. There will be 1GB ($80) and 2GB ($150) versions when they become available in March, and versions as copious as 8GB are possible.