Bulots. Otherwise known as winkle or periwinkle. I remember gathering dozens of these at the beach myself as a kid.
Escargots - Love them. Cooked with garlic butter, wine, and spinach. Could eat this all day.
Fois Gras - Extremely fine and smooth tasting. People will hear "L-I-V-E-R" and run for the hills. It couldn't be more different than typical liver.
Octopus (tentacles) - I remember a girl I was hot for bringing this as traditional dish in high school French class. Quite weird to see at first. I tried it to impress her and found out it wasn't bad at all.