Homemade PowerPoint Games are a special kind of interactive software called interactive modules. An interactive module, similar to any reusable learning object, is any self-contained, short, interactive experience that is relevant to school-based learning — they are not lessons, but resources for lessons and learning. The games found on this site can be modified to fit any content.

http://it.coe.uga.edu/wwild/pptgames/resources.html

The Hot Potatoes application enables you to create interactive multiple-choice, short-answer, jumbled-sentence, crossword, matching/ordering and gap-fill exercises for the World Wide Web. Hot Potatoes is freeware, and you may use it for any purpose or project you like.

http://hotpot.uvic.ca/index.php

Using easy to learn drag-and-drop actions, you can create professional looking games within very little time. You can make games with backgrounds, animated graphics, music and sound effects, and even 3D games! And when you’ve become more experienced, there is a built-in programming language, which gives you the full flexibility of creating games with Game Maker. What is best, is the fact that Game Maker can be used free of charge.

http://www.yoyogames.com/gamemaker