Google Desktop
After reading about the Google Desktop, I was immediately disappointed that there was only a release for Windoze. Even though I had no intention of using it on my Mac(Mac searching rocks already), I always see companies in a better light if they support more than just Windoze.
One really cool extension might be corporate shared drives. At every company that I have worked for, there is always a company wide shared drive that contain's massive quantities of documents. Normally, searching this document wasteland would take days, months, or lifetimes. Since I believe this feature would bring great value, I think companies would pay good money for google's search functionality in this environment.
Im indexing my Windoze box as we speak, more details to come.