Macintoshes...

The 512K uses an older mouse that is internally compatible with a PC bus mouse or an Amiga mouse, just one button. I do not know the pinout of the Mac, but it should be a trivial exercise to build a pin swabber. You could build a pin swabber for an Amiga mouse with two 9-25 pin adapters and a 25 pin "user configurable" plug box (two connectors, a circuit board, a bunch of jumper wires, all the size of a large null modem enclosure). The keyboard is Mac proprietary. The SE, as another poster pointed out, used ADB. There are clone mice and keyboards about, but you'll drop as much as the SE is worth trying to pick up a new mouse and keyboard for it. The SE can go to 4Mb, take an internal 3.5" SCSI drive (but non-apple drives need third-party formatters), and is somewhat useful. The 512K can take some snap-in accessories (I have a Dove board w/512K and SCSI), but they are rare now. Oh, only some 512K's (512Ke) have double-sided drives. Few SE's have FDHD drives (1.44Mb). Enjoy, -ethan