Ubiquity for Firefox
[youtube=http://www.youtube.com/watch?v=fvjdXNnRMfU]
I’ve recently tried this Firefox application prototype called Ubiquity and I like what I see so far. I especially use the def-function and the wiki-function. Where ever I am on the internet and I find a word that I want explained, I simply highlight it and press Option+Spacebar and Ubiquity pops up and I just write def or wiki and I get the answer without having to leave the page I’m on.