Games like Dance Dance Revolution, Guitar Hero, Karaoke Revolution and Audiosurf aren't just music games, they're games that take existing music, and recontextualize it into gameplay, giving players a new way to experience music they might already be familiar with, or exposing them to new music with the tantalizing promise of a fun game. Without music, these games are just about timing a certain color or shape with a certain button press. They're playable with the sound off, but they're not nearly as compelling.

In the past year or so, some game developers have started toying with applying this same approach to text.

The interesting thing about these kind of competitions is that you get to see what a really raw game looks like. There usually isn't enough time to have the game completely polished by the deadline. Often times the developer was never able to implement some core idea, or they quickly realized that the game they were building wasn't quite what they thought it was going to be. It is always useful for a designer to get a bit of insight into the design processes used by other designers.

Joystiq has a great set of screenshots and summaries of the finalists for the 2009 IndieCade Festival. Each one of these is a wonderful example of how a game can be so much more than a little diversion. Most of the finalists are games with something important to say or teach.

ElectroCity is a fun little sim game from New Zealand designed to "spark an interest and lay an unbiased foundation for later learning" about the topics of energy policy and environmental impact. It plays like a very simplified version of SimCity, instead oh having to plan out every detail, you just chose how to use a few large squares of land, either for mining, building power plants, or using the land to create jobs, increase tourism, or decrease environmental impact. You have to balance population growth, happiness, and energy use with environmental impact, and the city budget. You get graded in each category at the end with a simple A+ through F scale.