Mac Multipac is a pacman emulator. It was originally written for DOS, I ported it to the Macintosh. It can handle the following games:
Source Code is available.
The current version is 8.1.
NOTE: While Multipac was cool in its time, it is now obsolete. Actually, it became "MAME" which has got to be the coolest arcade emulator out there. So Multipac is not of much use any more, unless you want to run at 3x3 pixel size, or unless you are having a bit of a nostalgia kick and want to see where MAME came from.
Some good Links:
The about box pict (cause I think its cool):