The measurements of the Sony XDV-100 are 98.3×61×15.1mm and the sleek TV weighs only 110g. Features of this Sony pocket TV include a 2.83 inch screen with QVGA resolution, EPG, built-in speaker and earphone jack.
The battery life is 5.5 hours.
If you prefer a small phone the XDV-100 pocket TV might be interesting. There are several digital TV mobile phones on the market in Japan, like the Casio W51CA or the very cool Sharp Aquos W51SH that offer the same screen size or even bigger.
Sony will start selling the XDV-100 on April 10th in silver and black. The price is supposed to be approximately 40,000 Yen. (~$343).
More details in this Sony press-release (Japanese).