code.google.com/p/qsb-mac/

Google says:
<<Google Quick Search Box is an open source search box that allows you to search data on your computer and across the web.

This app is very experimental, but through it you will be able to see many of the areas we are exploring: contextual search, actions, and extensibility. It is by no means feature-complete, but is a very good indication of things to come.>>

[via googlesystem.blogspot.com/2009 ...]

Nice!