They Say: Google Quick Search Box is an open source search box that allows you to search data on your computer and across the web.
Every Mac user has used the built in Spotlight feature and most have probably tried third party alternatives such as LaunchBar(Paid) and Quicksilver(Free). These third party apps allow you to quickly perform a number of given tasks such as opening applications, documents, websites, songs from your iTunes collection and even do basic math. Spotlight does a great job at launching applications and documents but it lacks in the “other” department and it’s not always the fastest since it’s a giant index of your entire computer. These third party apps were introduced because they not only do these “other” tasks but they also do the core tasks such as launching applications quicker. They are also customizable unlike Spotlight. Recently Google has decided to throw their hat into the ring by releasing their version called Google Quick Search Box.
Google Quick Search Box is a free open source project which looks and works great and all though it’s only been out for a few months it already seems on-par with the other free alternatives and pretty close to the paid ones. First, it’s free. That’s an obvious one. Second, since it’s open source anyone can change and few the source and even contribute back to the app to make it even better. Third, it’s coming from Google so you know there is a lot of support behind it and unlike some of the other apps that are out there, Google Quick Search Box shouldn’t stop getting updates anytime soon.
I’ve been using QuickSilver since I’ve had a Mac and it’s been a love hate relationship. It’s a great app and it helps me out with my work but sometimes it doesn’t work well and it guesses what app I wanted to launch incorrectly and I end up starting something I didn’t want to. With that said QuickSilver is still better than SpotLight. Google Quick Search Box(they couldn’t think of a shorter name?) does everything QuickSilver seems to do but to me it just seems cleaner, faster and since it’s open source and a Google product I can see some great plugins being added. I’ve already replaced QuickSilver with Google Quick Search Box and I’ve been happy with it so far. I’ve used it to launch websites, do math instead of launching the calculator, check the weather and of course launch applications.
I look forward to doing a full review on the Google Quick Search Box once it’s had a little more time to mature. If I get some spare cycles I might even write my own plugin for it. 
Go download your free copy of Google Quick Search Box and give it a try for yourself.