RealNetworks is expanding its partnership with Best Buy. Working with music player maker SanDisk, the companies are going to debut a new music system based on RealNetworks' Rhapsody music service.

Best Buy is opening a Rhapsody-powered digital music store. SanDisk is launching the Sansa e200R Rhapsody digital music players on Oct. 15. The players are designed to work seamlessly with the Rhapsody service, and ultimately make a competitive run against Apple Computer's dominant iPod/iTunes combination. RealNetworks will also have to compete against Microsoft's upcoming Zune music system on store shelves.

It doesn't hurt to have one of the biggest electronics retailers in your corner for that fight.