Got to thinking about this last night.
My ex housemate has a genuine phobia of midgets. It sounds funny, until one time she saw one walking towards her and ran into the road in panic, and was nearly hit by a bus. Then it's hilarious.
I'm scared of people dressed up in costumes, like at Disneyland or family pubs. What freaks me out about them, is the social compliance aspect. We're supposed to act like they're actualy a giant teddy bear, and if you don't want to treat them like that, and let them cuddle you (urgh) then apparently that's you being strange. It could be a bloke in his 40s who lives in his Mum's basement, but I'm supposed to let him touch me becuase of what he's wearing? If he was wearing a nappy, would I have to treat him like a baby? It's weird.
Strange things my friends are scared of include buttons, cotton wool and balloons.
Any odd ones to add?