How do I convert MIDI files to MP3?

[macktheknife]

The title of the thread says it all--I'm trying to convert some old MIDI files I have (mostly game tunes I downloaded off the net) into MP3 files. How can I do this, and what programs will I need? I have both a PC and Mac, so a solution for either platform will do.

Thanks.

[yzeater]

You can export from Quicktime Pro, that should work