I've been doing a bit of screencasting lately and find that every once in a while, my laptop starts to stutter a bit here and there, as it chokes on the many background service that are inherent to a Windows-based PC.
Back in the day, I used to play a fair amount of MS Flight Simulator, Half-Life 2, and other heavy games, and stumbled across AlacrityPC via an online forum.
This great little piece of code allows you to shut down and terminate unnecessary services and programs with a click of a mouse before you run a resource intensive applications.
After I thought about it, I figured that what was good for the gaming stuff would be great for when I am doing screencast tutorials, working with multimedia authoring applications. Additionally, using this tool is pretty awesome to free up resources when I am presenting at conferences.