PocketPC Windows Mobile Game Emulation

here are two of the popular ones..

PocketSNES, to install, extract the files into a folder in your memory card. then run the .exe file!
You can load all those SNES games you had previously into the phone! quite nice, you can download the SNES games ROMs from here (or google for it :P). download them and copy them to a directory in your memory card. then load them from PocketSNES by navigating to the folder.

GenesisPlus, to install, extract the files into a folder in your memory card. then run the .exe file!
same as above :P but using Sega Genesis/Megadrive ROMS. look for those ROMs on google.