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

[d21lewis]

Castlevania II: CTMV W26K R5KN SIBK

And DKC had some cool codes: B,A,D, B,U,D,D,Y -D,A,R,B,Y D,A,Y,S come to mind.

Had a few others stuck in my noggin but I guess they're finally starting to fade away.