To be honest, I wasn’t the first one who came up with this idea. There already is another application called Mouse Jiggler — it also disables the screensaver and I even used it sometimes, but there was one thing that annoyed me about it. Mouse Jiggler is written in C# and requires the .NET framework. StayAwake is written in C using pure Windows API and has no dependencies. The only thing you need to run it is a PC with Windows. It also doesn’t load a lot of DLLs, so it uses much less memory (usually below 1MB).
You can also visit the StayAwake page on this blog.