here is a thread dedicated to weird game genie codes, i thought about this because i have recently found a list of old codes i found back in the 8-bit days
these can only be codes you have found yourself...
first game:
megaman 2
GAPGON = glitchy enemies
NOGPAG = remixed in game music, dont select next in paused mode
SKGEPP = press start during game to reset
STISTV = mega appears on screen then game resets
EAPEAP = cant select a robot master
NUGPIG = weird music, lives display as zero
NUGPOG = ???
AEAEAE = sweetness on select robot masters, and item 3 from start
EGGEGG = graphic glitch on master screen
NOGAYS = very random f/x (i played heatmans stage and it went well weird)
APIKEY = mega is invisible, and levels deteriorate
OPIKEY = try on airmans stage :D
EPIKEY = sweet!!!!!
AEPOZZ = mega freezes while music plays
Oh Baz, if only I hadn't left my GG notebooks in storage. I hosted a plethora of random oddities which I created durring my "bored with the new crapp" days, on the NES. I'll look into it, however.