Yarnbombing has been gaining momentum as a form of street art all over the world, but Polish crocheting artist Olek demonstrates what a real challenge is: in mid July she crocheted an entire locomotive in Lodz, Poland, that will be on display through August 19th. This is by far the largest project this New York-based artist has completed. It took Olek and her four assistants 2 days of round the clock work to finish the installation.