When Sheldon serves himself some spaghetti, the spoon is in the dish, then suddenly hovering over his plate, then back in the dish again.
At the rental suit shop Sheldon explains that he is wearing long underwear in order to avoid coming in touch with someone else's sweat when trying the suit. Raj then says that his reaction is not as entertaining as when he rents bowling shoes. But in The Wheaton Recurrence (2010) we learn that Sheldon actually has his own bowling shoes which he disinfects before wearing them anyway.