3D GameStudio
Rapid 2D and 3D games development on three different levels: 'Click together' games in the level editor - for simple games Create games in an easy C-like scripting language - for ambitious beginners Program games in C++ or Delphi - for experienced programmers
CMU SCS OZ Project
Develops technology and art to help create high quality interactive drama. This especially means building believable agents in dramatically interesting micro-worlds.
GameMaker
Card based development system which allows you to create simple adventure games with graphics, buttons, and text. For Apple Macintosh.
Interactive Fiction Authoring with IFML
XML-based Interactive Fiction Markup Language (IFML) used to create text adventures that run in your browser. Includes a sample game with IFML code, documentation, tutorials, downloads, mailing list, and a forum.
Interactive Storytelling Tools for Writers
Software for creating and using interactive storyworlds.
Kalevala - design the doom of heroes
Design, publish and play on-line adventure campaigns. Features puzzles, quests, magic and monsters. Your adventures can span entire maps/worlds and contain many separate dungeons.
Sludge
SLUDGE (standing for Scripting Language for Unhindered Development of a Gaming Environment) is a system by which anyone (within reason) can make an adventure game.
The Unofficial World Builder Home Page
Downloads, faqs and links to worlds built with this engine. For Macintosh.
Visionaire
Use Visionaire to create a complex adventure game without the need of any programing experience. This site offers information about how to use the software and what you can do with.
Wintermute Engine
Wintermute Engine Development Kit is a set of tools for creating and running graphical "point&click" adventure games. The kit includes the runtime interpreter (Wintermute Engine, or WME) and GUI editors for managing and creating the game content (WME tools) as well as the documentation, demonstrational data and prefabricated templates.