- Pyscho world... On the begin screen where the ladder leads up push f4 or f5 to change to color off the girl. There are several colors though... (go to power mode) now add powers to your skills by pushing numbers after picking up a [B] sign ... 0 totally refills your powerbar.
- With zanac-ex stop your game and push select... you can now alter the colors.
- Aleste 2 (game disk 1 or 2) hold select for a sound test and a 'difficulty select'
- Aleste gaiden.. dunno if it was left right (for about 24 times) or only left 24 times 
you just have to try 
- Aleste 1 hold S T and SPACE for a sound test.
Rune Master 2 - Push F1 and F2 simultaneously during the intro screen for a sound test
Rune Master 3 - Boot disk 2 with B, G and M pressed (or it was S, T and spacebar) for a sound test
Zanac Ex - Push SELECT @ game over for a different tune
/me gotta find that list he made with all them sound tests 