Tempest

Cheat mode:
Get a high score with the following attributes to unlock the corresponding cheat function. The first two digits of your high score must be greater than 16. The middle two digits of your high score must be greater than 29 but less than 60. The final two digits of your high score must be the following numbers to unlock the corresponding cheat function.

Digits	Effect
00	Freeze the screen
01	View bookkeeping totals
05	Play during attract mode
46	Play during attract mode, random colors
48	Play during attract mode, 255 lives
06, 11, 12, 16, 17, or 18	40 free credits
14 and 15	Credit sound without credit
41	Switch last two digits of score
42	Increase score quickly
46	Level select up to level 81
50 or 51	Auto pilot
60	Objects drift down
66	Objects drift right
67	Objects jump
68 or 69	Objects drift up