This is actually the third and a half version of my ancient "game" library. The first version was intended to be a library that allowed games to be written portably for DOS or Windows. The second iteration dropped DOS support and focused on providing a lot of functionality for multimedia/graphical applications running under Windows, including streaming playback of many video and audio formats, scripting support, and other fancy things. The next version departed from the game genre and aimed to abstract away the operating system, allowing programs to be written portably. I got it compiling under Windows and Linux and had plans for other unixes, including Mac OS X to be supported as well. The game-specific parts weren't done, but the OS abstraction was working and very useful. Eventually, though, I realized that with mono coming along so nicely, I might as well build this atop the .NET framework, which would have the added benefit of being language-agnostic and not tying any potential users to C++ as well as reducing the amount of work I would have to do.
After the advent of modern 3D games, I haven't updated this much, but it's still kinda useful.