Latest development system for Texas Instruments "wireless" micro-controller comes in the form of a watch. Yes, a regular watch that can track several variables besides the time passing.
Besides the watch, the kit includes an USB RF interface and a USB emulator for software debugging. The watch itself includes a 3-axis accelerometer together with temperature, pressure and battery-level measurements.
At $49 it is a steal. No wonder they are out of stock. There is a wiki too.