The Mini vMac emulator collection allows modern computers to run software made for early Macintosh computers, the computers that Apple sold from 1984 to 1996 based upon Motorola's 680x0 microprocessors...
Besides the Macintosh Plus, there are also emulations of the Macintosh 128K, 512K, 512Ke, SE, Classic, and SE FDHD. Work is in progress on Macintosh II emulation.
I was pleasantly surprised by this one. Very simple, very small, yet works nicely. You will need a Macintosh Plus BIOS.