Unilateral smoking ban, UK
When the British government announced that, as of July 2007, smoking would be prohibited in all enclosed public spaces, no-one really believed it would happen. But it did, and the only cloud to this silver lining has been the proliferation of hideous 'no smoking' signs on every door up and down the land. OK, so everyone likes a crafty cigarette now and again, but if you absolutely must, you can still just nip outside. For now.