Most Pocket PC's do not have a lot of room for mp3 file storage even with expansion options. One solution is to stream a large collection from a regular PC over a secured home network with SHOUTcast, and use software like this
on the Pocket PC to access the stream. When you stream over a secured home network you are not subject to the upstream bandwidth limitations of your internet connection, and since it cannot be considered a public broadcast there are no licensing restrictions.
A WiFi or bluetooth capable Pocket PC with some nice earbuds accessing a streamed multi-gigabit collection of mp3 files is a much nicer system than your typical iPod.
If that sounds interesting, then you may also want to check out the software we develop, AIVMS
. It is an artificial intelligence that is capable of operating as a broadcast stream DJ. It can introduce your songs with information it collects about the song artist from the internet, and you can include AI announced news, weather, and even traffic reports if desired, just like a normal FM radio station.