Sumotori Dreams is a game designed for Win32 whose complete executable is less than 96kB uncompressed. The game was presented at Breakpoint 2007. The machines that they used to run things in the competition are XP SP2 with DirectX 9, website
so it is not unreasonable to expect that the game hooks into many of the available APIs to generate the graphics. It is also possible that the texture maps could be pulled from the XP installation. Even though this game is smaller in size than most spyware, what is ed
it is truly impressive how fun it is to play.