I know a few where they compliment each other. A dentist that married a lawyer. The lawyer could always use a dentist and you never know if a malpractice lawsuit ever comes up, haha. Or a pharmaceutical rep that married a health insurance rep. My wife got her degree in phycology, then went back to be a dental hygienist. While the hygiene part has little to do with programming, she helps on my sites (which are geared towards dentistry) and... my teeth are always clean, haha.
I sometimes wish she got into graphic design - it would of allowed me to take on more freelance work I think, but it's never stopped me otherwise, so no big deal.
I think it's important to find someone you can get along with and love. If they can understand what you actually do and the struggle, all the better.
I don't want to put anyone down - but say a rocket engineer married a secretary, that might make for some one sided conversations. It's good to find someone that compliments you and your skill set.