Mini vMac is an excellent emulator for the Mac Plus. I have quite a collection of old mac software that I backed up from my original floppies, and I'm glad I did. Who knows how much longer those would have survived before they all had errors.

Check out mac garden if you are interested in old mac stuff, it's great.

If you ever make a clone of an old paint program (maybe in a web browser? should be possible nowadays) let me know :-)