Pitfall

Unlimited lives:
Load or reset the game, then execute the following BASIC command before running or restarting the program.
POKE 5393,255

Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC command before running or restarting the program.
POKE 2660,250

Cheat mode:
Load or reset the game, then execute the following BASIC command before running or restarting the program.
POKE 34757,165