I've heard of, and had, most of those. No pineapple sandwiches, and I probably won't. Although I think a slice of pineapple might be good on a ham sandwich...
I'll definitely pass on the mayo sandwich. Just gross. I'm not a big fan of mayo in general. If I order a sub, for example, I ask for it with a thin layer, and if I make macaroni salad, it's fairly dry. Hate it gloppy and mushy.
No offense, Onebyone, but I'm passing on that pb and onion!
I do love a good tomato sandwich, when fresh tomatoes are in season. One of the best things in summer!