You should've seen Peegee and my discussion when I discovered a similiar feature on the New York Times' website.

Paraphrasing
Me: Wow look at what I just found!
PG: What?
Me: When I click on a word, it defines it for me.
PG: Is it Firefox?
Me: Yeah. Maybe a new feature!
PG: Mmkay.

Can't you just imagine the excitement in his voice?