I'm really boring with my J/P's. I have either tuna, mayo and sweetcorn or baked beans and cheese. Very rarely I might have low cal coleslaw and cheese or some prawns.
I do like it when the potato is scooped out and mixed with cheese, onions, bacon etc but I like to spray the skins with fry light and put them back in the oven to crisp up then put the filling back in and top with cheese then grill it. But I'm too lazy to do it very often.