WiimoteCommander

WiimoteCommander is a tool for connecting wiimotes (with extensions) to a PC.
Key features:

Portable: 100% pure Java. It runs under Linux, Windows, MAC...
Connect up to seven wiimotes simultaneously.
Display events of all connected wiimotes and extensions.
Display status of all connected wiimotes (Battery levels, Bluetooth addresses, ...).
Control wiimotes speakers, rumble and LEDs.
See a 3D view of connected wiimotes with real time moves.
Free: The LGPL license permit you to freely use and include this software in your products.

http://wiimotecommande.sourceforge.net/