you know those old gameboys everybody had one no backlight non-rechagable batteries horrible graphics well the copy write has expired and a bus load of designers are afraid that their games they worked so hard on will be forgotten.well most have authorized they to be down loaded and played on your computer or other device if you happen to know how to do it.
they also have ds games and even ps2 games but unfortunately you need one POWERFUL computer to operate the emulator the game system and a bit of hard drive space for the games for the most part esp. the GBA games  they are simple to set up and use my little brother can operate it (chris).