Thief: The Dark Project

Level skip cheat:

Press CTRL-ALT-SHIFT-END to advance to the next mission.

Alternate starting point:

To start the game at a mission other than Lord Bafford's manor, exit the
game and edit the file dark.cfg. Add the line:

starting_mission X

where X is the number of the mission where you wish to begin. Save and exit
the file, then start the game. When you select New Game, you will start at
the mission you specified.

Money cheat:

To give yourself as much money as you want, exit the game and edit the file
dark.cfg. Add the line:

cash_bonus X

where X is the amount of gold you want. Save and exit the file, then start
the game. When you get to the "Loadout" screen, immediately hit ESC, then
SAVE, then quit back to the Desktop. Re-enter the program and load the game
you just saved. You'll return to the Loadout screen, and another 3000 gold
will be added to your purse.