I'm the 'movie geek' in my circle of of friends, which can be kind of lonely as there are times when I will get excited about something ("Hey, HMV has the Klaus Kinski/Warner Herzog collection on sale for twenty bucks!") and none of them know what I'm talking about.
I used to use my powers for evil, making my friends watch stuff that only I liked, stuff that I thought they should see merely because it was 'important.' I've grown up a bit since then. Now I use my film knowledge to try and pick something that's good but enjoyable for everyone (You like rom-coms? You like Audrey Hepburn? Let's watch the original Sabrina.).
As for moneatary rewards, I make a little extra money doing the occasional DVD review for my local paper. But what I find much more rewarding is that every time I see a movie, I gain a new way of looking at the world, like my mind has gained one more facet. With every movie I see I feel like my understanding of film as a whole grows. That alone is enough of rush.
Plus, it is sweet cleaning up at trivia nights.