Up for grabs on ebay is a complete copy of Mega Man for the Sega Game Gear. Considered to be one of the rarer games in the series, the game, released by US Gold in 1995, is a port of MM4 and MM5 featuring enhanced visuals.
The auction contains pretty much everything you could as for - box, manual, cartridge and even a handy dandy cartridge protector. Of course, all of this comes at a price; $99 plus the additional shipping.
Collector's might not want to pass this one up.