My daughter used to suck on lemons all the time. She claims she can't taste "sour", and that things like lemons and limes are just sweet to her. She never really ate anything too out of the ordinary.
My son is a notoriously picky eater, especially now. He's vegan now, and hasn't eaten meat since he was eleven or twelve. He's always been funny about it. "No two foods shall touch unless cooked together" has always been his eating philosophy, but he oddly likes things like peanut butter and banana sandwiches. When he was little, he loved tuna and apples mixed with mayo and a bit of vinegar on toast.