What cheat codes have remained in your memory to this day?

[umegames]

up down left right hold A start (sonic 1 stage select)

19 B, 65 B, 9 B, 17 B ( Sonic 2 stage select)

highlight zangief, left left, down down, right right, down down, left left, up up, right right, up, right ( marvel vs capcom - secret character Roll)