Use a completely unmodified wireless Wii Nunchuck as a control system for any Arduino based project. No added radio transmitter/receiver pairs etc.
This instructable does assume some experience with the Arduino microcontroller.
The radio receiver that comes with the wireless 'chuck is connected to an Arduino which then reads data from the 'chuck.
There are descriptions on the net of how to use an Arduino to "read" data from a standard wired Nunchuck. This is a handheld device which is meant to connect via a short cable to a socket in the base of a Wii controller (the rectangular thing), which then sends data via Bluetooth to the Wii (or indeed a PC).
A special adapter has been made by with six contacts on it to enable the experimenter to connect the plug on the end of a Nunchuck to the pins of an Arduino board.
Here is an example of one of these:
It is easy to use a Nunchuck adapter to connect a wired or wireless chuck to an Arduino. However for a more stable connection I suggest:
Buy a Wii Nunchuck extender cable. This has a Nunchuck socket on one end and a plug on the other. Cut the cable so you now have the socket on one end and some free wires on the other which you can solder to your Arduino.