Do you want to have roms, or you want to discover old games?
Now you can do both.
.A26=Atari 2600 rom
.sfc=SNES rom
.nes=Nes rom (Duh)
.bin=Atari 2600 Rom
.gb=Game Boy rom
.gbc=Game Boy Color rom
.gba=Game Boy Advance rom
.md=Sega Genesis rom
.smd=Sega Genesis rom
.nds=NDS rom (duh)