The ZTE Peel is an iPod touch case with a built-in 3G hotspot. It's a little gimped compared to a full-on hotspot, though, and pricier too. It costs $80, only supports two devices at a time, and a piddly 1GB of data runs $30 per month (albeit, contract free). To compare, Sprint's OverDrive with 4G service costs $50, and for $60 a month you get 5GB of data over 3G and unlimited 4G data.
The biggest compromise? It also turns the super skinny iPod touch into kind of a fattie. [SPrint]