111+Zones - play tic-tac-toe (if enabled in the CFP).
243+Zones - utility screen with clock, cpu meter, net connect and claw foot portal.
411+Zones - shows info about the system, including version #s.
611+Zones + 116+Zones - show service screen.
777+Zones - demo settings - has restore factory defaults button.
876+Zones - require setup after next reboot.
ENABLE/DISABLE DISK SPINDOWN
JULIE - prints "Spencer loves Julie."
SPORTSGUARD ON/OFF - turns on main menu/setup/change default record options to include SportsGuard, a soft padding of sports events.
TIC TAC TOE - enables 111+Zones to play tic-tac-toe.
ME LIKE COOKIES - prints one of many funny phrases.
3RT8OMT - prints I am for you. I think it also toggles a registry setting.
I found out how to display a credits Easter egg showing people associated with hardware, software, "user experience", Q&A, HR and special thanks.
Go to main menu / setup / change display brightness and hit 888+zones. Try FF, REW, STOP, Display and Input.