Several months ago I read a someone's post calling ActiveWords the best application that they could live without. ActiveWords is an enormously powerful program that runs just below the surface to launch programs, replay text, spell-check and so much more. It's also a system hog and I didn't reinstall it the last time I rebuilt Windows (or was it two times ago?).
Several months ago Lifehacker pointed me to a great little application launcher called Launchy. It is fantastic.
Launchy is first of all an application launcher. Hit the default keyboard combination (Alt-spacebar) and a little dialogue box pops up.
Type in the first couple of letters of the application you're looking for and hit enter. The app launches. Launchy automatically indexes your start menu and gives you access to your applications without every touching the mouse. It also indexes your other things, including your control panel. Need to change display settings? Simply type 'display' and launchy will take you there.
There are also some other handy functions built in, like a calculator.
Hit Alt-Spacebar and enter the numbers you want to operate on. Launchy will do the rest. You can check out some other features and screen shots at Tweaking Launchy. You won't want to be without this.