ADVENTURE GAME STUDIO
Adventure Game Studio allows you to create your own point-and-click adventure games, similar to the early 90's Sierra and Lucasarts adventures. It consists of an easy-to-use editor to create your games, and a run-time engine to play them.
The game interface is fully customizable, with classic Sierra and Verb Coin templates provided by default. AGS manages most of the game so that you don't have to - it does all the donkey work like load/save game functions, pathfinding and scrolling rooms so that you can concentrate on the parts of your game that make it unique.
Set up your rooms, characters and sprites visually in the editor, then add some script to handle game events and you're done! You can even create a standalone EXE file containing your entire game, which you can then distribute to your adoring fans worldwide.