This is way cool! Check out this article on the Indie Game Jam.
Basically the Indie Game Jam was a 4 day programming and game design jam to see how many new and interesting games a few people could make given a small engine to start with and a little time. This particular engine could draw what appears to be a heightmap based terrain and 100,000 sprites!!! Given that type of engine the people made around 12 games in those 4 days. At the end of the article is a link to the site.