If their website is any indication, Jefferson County Schools in Tennessee must be a very good place to teach. The website contains numerous, good, technology resources. One such resource is a collection of templates for building PowerPoint games based on the concepts of Jeopardy, Who Wants to be a Millionaire, Wheel of Fortune, Bingo, and $25,000 Pyramid. All of these templates can be downloaded from the site and altered to suit your needs.

Applications for Education
Students generally find studying to be a lot more enjoyable when they can do it in a game format. These templates provide a good way to build review games that your whole class can play at once.

Here are some related resources that may be of interest to you:
200+ Games for Your Blog or Website
Games for the Brain