My wife rolls her eyes and tries to keep track of how much I have spent on my hobbies, so that she can "keep up" and not feel guilty about spending money on her own stuff.
I really got her the other night though, it was awesome. We were at a party with all HER co-workers and friends, none of my friends there.
Now you also have to understand that all my friends are fellow Ph.D students in a completely technical/scientific field, all of us working on either LEDs, laser diodes, or solar cells, so we're all complete nerds and our conversations almost always end up back on research and science, even when we're out drinking and partying. And my wife's friends are all normal people with NO geekiness or nerdiness whatsoever, I doubt any of them took any hard science or math after high school. So we're at this party, I have some lasers with me, and much to my wife's chagrin, all her friends LOVED my multiple colors of lasers that I have with me. Her friends ended up quizzing me on how lasers work and all about my research work for over an hour, and then INSISTED that I bring my whole laser collection to the next party that they all have together so everybody can play with them and hear all about them again. My wife hates hanging out with my friends because we only talk about lasers and nerdy stuff, and yet her friends all end up talking about lasers more than even MY friends did at their last party. It was AWESOME.