I just wrote a Freebase search command for Ubiquity:
Ubiquity is going to be awesome for Firefox power-users. One of the best things about Firefox is the extension eco-system and Ubiquity is going to make writing extensions much easier.
P.S. Ubiquity is only on v0.1 and executes 3rd-party code on your machine. You probably shouldn’t install it in your main Firefox profile just yet.