My husband and I have been all over Asmiov's robot stories of late. We were watching the movie I, Robot last night, and musing as to why noone has made adaptations of the Caves of Steel series, which we thought would adapt well to the big screen.
Somehow, the discussion morphed into positronic brains, and I said something about my positronic brain. My husband replied by saying "you have a negatronic brain". I looked at him in dismay, wondering what in the hell he meant by that. He explained that because I always had such a negative attitude about things, there is no way I could have a positronic brain.
I'm not sure which is worse, the insult itself, or the geeky context of the insult.