Lol. I can't really remember where most of these are from:
Jay-walking is still illegal in Australia, but the last time anyone was fined was in the 1970's.
Similarly, so is vagrancy.
Apparently, somewhere, it's legal to have sex with an animal, but only if the animal is female, and weighs less than 65 kg.
Incest laws...
In the UK,
Having sex with Parents, or your brothers and sisters is illegal (even if they're step-brothers/sisters).
Doing it with your grandfather is as well.
But doing it with Grandma is fine...
Marrying your uncle, aunt or cousins is also illegal, but having sex with them is not...
Mmm. Strange, but I guess there are much funnier ones around. XD>