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.
So, how much does it cost? Nothing. That's right, AGS is free, and you can even create commercial games with it (subject to license terms).
Want to play games made with AGS?
Head on over to the Games page and try some out, or check out the showcase links on the right of this page.
Want to make games with AGS?
See the AGS feature list, check out the tutorial, and head over to the download page. If that's not enough, see the resources page for tips and tricks.
Before you start, bear in mind that AGS is not for everyone. In order to make your game respond to the player's input, you'll need to learn the scripting language. Whilst we try to make this as easy as possible, some people will always find themselves more suited to scripting than others. Don't be discouraged, just don't expect to make the best game ever in your first few weeks!
http://www.bigbluecup.com/acfeat.htm