Upon connecting to the Slacker service via WiFi or a PC's USB port (the latter connection method does not support the Mac), the Slacker Portable caches hours of music for each of these stations. "Filling up" a station from scratch took about 10 minutes, but partial refills are faster. While the Sansa Connect relied on a premium music subscription to transfer tracks to the device, the basic tier of Slacker service -- which includes two commercials and up to six skips per hour -- is free.

Slacker has a premium service available for about $7 per month that eliminates the commercials and allows an unlimited number of song skips. Slacker assures that customers won't experience constant bombardment of upgrade exhortations as its business model works well even with the free tier of service and a player purchase.

Slacker made some curious decisions in designing its portable, which is larger and chunkier than, say, an iPod classic. The device includes a large 4-inch screen even though it cannot play video or even display photos, although it does nicely highlight album art. Slacker defends the decision in part by noting that the larger screen is helpful for reading background information about the artist. And indeed, Slacker displays extensive artist information from All Music Guide, but crams the information into the lower portion of the screen, requiring more scrolling. (Also, be sure to finish all that reading as before the track ends, as the artist info page will refresh as soon as a new song starts playing.)

Next week's column will further discuss the Slacker Portable controls and music listening experience as well as Slacker's plans to compete more directly with satellite radio.