It's to bad that this doesn't run as a daemon that can simply be queried through an API. Back in the day I remember a linux project called ... dashboard? (found it!
http://nat.org/dashboard/) That seemed like a great tool. For whatever it got scrapped and it's guts turned into Beagle. Since I no longer use linux on the desktop it's hard for me to evaluate, but it looks like it's now a tool similar to OSX's Spotlight.