GlobalSat BR-355 GPS mouse is very compact and waterproof. The unit is available at various online stores for about US$ 40.

The technical specifications are quite common for this type of device. SiRF Star III chipset has now loaded with version 3.1.1 and support WAAS enabled by default. It is accurate within the range of 5 meters. As for the starting time of the unit takes 40 seconds in cold, but almost a second after ignition.