If you've ever seen any of the shows about bike messengers they carry more then one lock. Chain around object through frame and front wheel, chain around object though frame and back wheel and finally a hoop lock around object and though the seat post.
The best one I ever saw was on some honesty show. The ex-thief/security expert found a bike locked to a 4' tall post with a hoop lock though the frame. He picked up the bike, slipped the lock off the post and off he went. Of course they waited around for the owner to point out how stupid they were.