At its 2007 line show, Sony unveiled three new shelf systems, all featuring Bluetooth connectivity, which will enable the systems to play digital audio files from other Bluetooth devices, such as computers, MP3 players, and cell phones. The three shelf systems--the CMT-BX5BT, CMT-HX7BT and CMT-DH7BT--will cost between $150 and $300 and be available in April.

The CMT-BX5BT is the entry-level model. It can play MP3 files--probably via Bluetooth or burned onto CDs--and has the ability to read ID3 tags, which means you'll get artist and track names on the display. There also are the standard features for a shelf system, such as a CD player, an AM/FM tuner with 30 presets, and a sleep timer. Sony claims the CMT-BX5BT will deliver 15 watts per channel.