I have been trying to figure out how to wirelessly operate an amplifier with a self-powered bluetooth/infrared receiver connected to a RJ12 RS-232 serial port covering Rx,Tx and GND.

Naturally, I thought that going down the IR route would probably be the easiest way to go wireless, since the amplifier is already fitted with a infrared receiver. However, I would also like to replace the cabled RS-232 serial connection to my laptop with a battery powered infrared, bluetooth or WiFi solution.

I have looked at commercial products such as the following:
[Link: lm-technologies.com]

I am not familiar with the various Arduino offerings, but they are quite interestering and cheap. Resently, I have come across the Arduino Bluetooth HC-05 module which looks promising.