At the menu screen, press P to enter a password.

Password	Effect
BEETLE	Start on Level 10.
BJBJBJ	Start on Level 20.
BLAAHH	Start on Level 180.
BLAMMO	Start on Level 100.
BLORT	Start on Level 80.
BOOOO	Start on Level 160.
BUURRP	Start on Level 120.
CRAAZY	Start on Level 60.
EERIE	Start on Level 30.
KRPLOP	Start on Level 240.
LEV200	Start on Level 200.
PTOOIE	Start on Level 90.
SPLAT	Start on Level 70.
TRICKY	Start on Level 40.
WEIRDO	Start on Level 50.
WHAAAA	Start on Level 140.
ZAPZAP	Start on Level 220.