15. Neil Patrick Harris and David Burtka
How sweet is this — Burtka asked NPH to marry him in the same exact spot they met. The actor explained: "We were on our way to an event at an Indian casino 45 minutes out of town in a limousine, and David wanted to stop for some reason that I didn't quite get. I thought he wanted to get some booze or something. And then he got on one knee and proposed, and I was so freaked out by it that I said, 'Yes,' but I didn't know what it meant."