I remember hearing one state had an old law that if you drive a car past a horse, and the horse was offended by the car, you had to stop the car, dismantle it, and throw a cover over it until the horse went away.
It's illegal to have chewing gum in Singapore, or so I've heard.
I can't remember what state had this one: it's illegal to have sex with the lights on.
Spokane has an old law that says it's illegal to spit on the boardwalks. Some folks say this law is still enforced, but I've never heard of anyone say that they've gotten a ticket for spitting on the sidewalk, much less a boardwalk.
And then you have sodomy laws. Yes, even in your own house.