IR Remotes and Arduino

I'm trying to develop a project where my Arduino will need to be signalled wirelessly by one of several devices. I think IR remote controls will be the best way.

I'd like to build a bunch of 1-button transmitters (probably with an 8-pin PIC or Atmel chip) and a single receiver built with an arduino. I don't know where to start though...I've read information about commercial coding schemes but the transmitters I've tried building haven't worked.

the code for both IR receiver and transmitter is here:

all you have to do is make the circuit

Keep in mind you'll need to detect collisions. If two send at the same time you'll get gibberish.

nima, That code looks like exactly what I want, though it will take a fair bit of work to get to what I need.

cheater, That occured to me. Any idea how close in time I'll be able to detect signals? It's fairly important for me to be able to tell "who went first", so I'm not even sure an IR solution will work.

For the transmitters, is it possible to run the arduino bootloader in an 8-pin package? All I need is 1 output for the LED and 1 input for the button.