WARNING: THIS POST CONTAINS A DESCRIPTION THAT MAY MAKE BIKE OWNERS WEEP.
Around here in San Francisco, it is common for bike thieves to have plumber's pipe cutters. They will cut through the frame, pull the bike free, cover the damage with tape, sell the bike at the flea market to idiots who will be subsequently injured by the secretly-unsound frame.
Also, they can easily use a modify automobile tire jack to shatter u-locks. So make sure your u-lock is small.
One reference out of many:
http://www.cyclelicio.us/2013/bike-thief-tools/
Hey, it's a Moulton. BRING IT INSIDE.