If your wife does something that she feels bad about, teasing her is OK but know when to stop.
One of my wife's number one goals during the ALA conference was to get an Advanced Readers Copy of Catching Fire by Suzanne Collins. However she was overwhelmed by the size and scope of the conference and did not arrive at the correct booth in time to get one.
So in my infinite wisdom I spent the rest of the weekend teasing her.
Yes she laughed at first, and did not even mind when the joke was starting to grow old, since she was at an event that held her enraptured. For four days I was able to get away with it, but as soon as we left and I teased her she started to become cross. You have to know where the line is and realize that the line changes based on the situation.