You probably don’t need this if you have Vista, but I’ve been wanting a good application launcher for XP for some time.
Launchy is an open source application that indexes your Start Menu automatically, and it was easy for me to tell it to index some folders of .exe’s also.
Now I just hit alt-space and then start typing the name of an app, hitting enter when the correct app shows up. You can also use Launchy to type in queries for Google or Wikipedia, among many other tasks.
Found this one on freewaregenius. You can download Launchy here.