Today, it seems, emulators on RISC OS are like buses: You wait for ages for one to come along, then three turn up all at once.
MAME stands for Multiple Arcade Machine Emulator, and does just what its name suggests: it can emulate several thousand arcade machines and when fed an image of the ROM and disk data from any of these machines, it attempts to play the game, reproducing as faithfully as possible what we would enjoy on the original machine. The RISC OS port can currently supports around 1700 ROMS, and more will be added in later versions. RISC OS 5 is recommended to run MAME because of its memory and resource requirements.
Snes9x is a Super Nintendo Entertainment System (SNES) emulator, which can play most games designed for the SNES and Super Famicom game systems – including some real gems, apparently, that were only ever released in Japan.