> Space Invaders emulator for ZX Spectrum +2A/+2B/+3:
It's running a patched version of the original game code on the Z80 and translating the video hardware etc. and emulating any missing extras (the shifter hardware)
it also doesn't run on stock hardware, you need modified hardware that can map ram at 0
so.. part of me doesn't really think it counts, it's hardly emulation, just a port that fails to work on the hardware you could buy at the time.