This article is from the General Pinball FAQ, by Keith Johnson keefer@access.digex.net with numerous contributions by others.
Yep. We currently only know of ones in Williams/Bally games. The following
steps describe what you can try to do. Most of them work only in attract
mode with no credits since you have to use the start button (therefore, free
play is also out of the question). Also, it is best to do them right after a
game, slam tilt, or power-cycle.
L = left flipper, R = right flipper, S = start button, B = both flippers.
A number in front indicates hit the button that many times.
TAF - 7L S 14R S 20L S = cows 13L S 1R S 2L S = credits
TAFG - same as above, PLUS 12L S 5R S 4L S = new cows
STTNG - B 8L R 5L R 5L R 6L 2R = Steve Ritchie games (works during normal play as well)
 
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