Caviar - don't think I've had it, but willing to spring for the freight if it's not too much.
Foie gras - had it once, nice, but overrated IMHO.
Tripe - Once. ONLY once. Won't be another time.
Escargot - Great stuff! I think of it as a garlic and butter delivery device!
Calamari - Great, if not chewy. Truly wonderful stuff.
Haggis - Willing to try it once, if a gun is pointed at me.
Collards - Never order the stuff, but I'll eat it if put down in front of me.
Chitterlings - Had it once. Looking forward to never having it again. Or smelling it cooking. Did that once on a submarine, part of "diversity."
Frog legs - pretty good.
Rabbit - OK, but doesn't hold that much appeal for me. Served it on the submarine - on Easter. Skipper wasn't too pleased at that.
Raw Oysters - Great stuff. More risky to eat these days, but in April when in Key West I'm downing a few dozen. As a side note, when my father went to college, he was initiated by being required to swallow a raw oyster. Then they pulled the thread back up, and made him swallow it again!
What I'm looking forward to trying: INSECTS! More dense protein than beef. Usually crunchy, but some are eaten squishy. I keep reading where we'll be eating them more in the future, simply as a potentially economical food supply. Popular in much of the (starving) world. Asia, Africa.