I'm not sure I'd work for my wife full-time, but a couple of weeks ago I took a temporary position/project in which she is technically my boss. She runs an admission office at a university, and needs extra folks to read applications through January, and because I've done similar work before and have the time, I've signed on to make a few extra bucks. So far it's gone well, and the school has internal rules under which she can't "review" or "discipline" me.
But I don't think working together full time would be a good idea. She and I have discussed that possibility in the past, and have always decided against it. In fact, a fantastic position became available at her institution for which I was ideally qualified, and I didn't even apply. This was mostly because I wanted to stay with my current gig, but I also didn't want to work at her school and risk possible problems or tension. I could tell she was apprehensive that I would apply, and we wouldn't have even been in the same department.
As other have said, if you do this, you need some clear boundaries, and unfortunately I think it's pretty risky.
