@usuario_msx2: one request, can you make a universal remote controller for DVD players?
From HW point of view IR remote control is actually pretty straight forward to make. You need an oscillator, IR-led and few transistors & resistors. Somewhere in 90's such a device was also available. I think it might have been called MIRC(?) It was a simple device that you could plug to a joystick port to send and receive remote control commands.
. It was described in one of the Dutch magazines I guess? 