Hah, never noticed that but Frodo's accent goes in and out and around the block too.
My all-time fav is still Tim Roth in Reservoir Dogs. What a hilariously bad accent. So over the top wrong on every level. "I'm faaahkking deeyiing!", "Matherfoker looks jus like Tha Thing." "Matherfacker I'm tryna watch Da Lost Bois!"