At least this Action Replay let me know which revision of Super Smash Bros Melee I seem to have, and also obtain all of the yellow Japan-only custom-machine parts availible for purchase in F-Zero GX (the only other Gamecube game I have)

they have all of the resident evils, all of the prince of persias, all of the legend of zeldas including twilight princess, eternal darkness: sanity's requiem, both metroids, the megaman collection, wario world, luigi's mansion, and all of the marios including double dash, sunshine, and strikers, and even both of the super smash bros

I've had loads of fun tweaking the variables in Super Smash Bros Melee

P.S. don't expect the debug code for Super Smash Bros Melee from this Action Replay!

For example, in Super Smash Brothers: Melee, you could use a debug code to play six players melee