This could be very easy. Which mac? If it's one with IR Support (Mac Minis have it, older macbook pros have it, unsure of the Mac Towers) your installer can use a program called remote buddy and map a remote button to start the program through an IR flasher from the processor. Couldn't get much easier. I do it quite often with mac mini's.

If its a computer that doesn't have IR support, then it's still possible but someone smarter than me would have to point you in that direction.