Photos: Portable satellite radio receivers

Previewed last August, the Sirius S50 is the company's first wearable receiver. Users can capture and store up to 50 hours of Sirius programming and MP3/WMA files. The device also can tune in to live radio broadcasts.

The Sirius S50 is priced at $359.99, including a car docking station. A home docking station also is available.

Earlier this month at the Consumer Electronics Show in Las Vegas, XM Satellite Radio unveiled a pair of devices that double as radio receivers and MP3 players. Both are part of its XM2go line and are expected to go on sale in March. A tie-in with the Napster online music service lets people bookmark songs they're listening to for later purchase. Pictured here is the $400 Pioneer Inno (4.5 ounces, 3.7 inches high by 2.2 inches wide and a half-inch deep), which stores up to 50 hours of programming.

XM Satellite Radio unveiled a second radio receiver/MP3 player at CES, the $400 Samsung Helix. It sports the same dimensions as the Inno and similarly stores 50 hours of programming. Both devices are due out in the first quarter.

The XM Roady XT, $80 from Delphi (now available with a $30 rebate), is the company's smallest plug-and-play unit, measuring roughly 2 inches by 4 inches. It can transmit a signal through any of 100 FM frequencies and can display both sports scores and stock prices on its two-line display. An optional $100 pack with a battery, headphones and a built-in antenna will be available from Belkin by March. The pack will allow the Roady XT to be used as a portable unit.

XM's original on-the-go unit, the Delphi XM MyFi. It costs $225 (available with a $50 rebate) and can be used in most outdoor locations, thanks to its built-in antenna, though reception can be uneven. It also can also record up to five hours of programming. To improve on-the-go signal reception for this and other older XM2go receivers, users can purchase a $25 Belkin headset that includes a built-in antenna.