Before I opened the thread, I tried to come up with an answer. My first thought was to repair cars. I figured that would be a great skill, however, if my car broke down... I don't think I'd really want to fix it. It would be hot or cold and dirty and I'd have to lay on the ground or cut my hands up. So I tried to think of something else and I thought, I'd like to be multi-lingual. Yea, that sounds like a great skill and you can stand up the whole time, if you want to.
I liked Jane's answer too. There are so many great skills... that I don't have.