Korean MP3 player manufacturer releases the iAudio U2, which is only as big as a lighter.

The iAudio U2 measures 73.8mm x 25.0mm x 18.0 mm and weighs 35g. it features a 128x64pixel graphic LCD. The U2 comes in 256MB, 512MB and 1GB storage sizes. The player supports MP3, WAV, WMA and ASF music file formats. The data transfer works fast over USB2.0. BBE, Mach3Bass, MP Enhance and 3D Surround sound effects are provided.
The lithium Polymer battery keeps the iAudio U2 playing for 20 hours. FM receiver and direct encoding are built-in as well.
The iAudio U2 is apparently on the market in Korea already. The 1GB version is listed with 399,000won (~$341).
More details on iAudio Product page (korean). More hi-res photos. Thanks Jason.

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