Online takeout middleman GrubHub has filed for an initial public offering that it hopes will raise $100 million. And to help it along, its rooting for some cold weather. The company hopes to be listed under the moniker GRUB on the stock market, it wrote in an S-1 filing with the SEC today. Fresh off its merger with Seamless last year, GrubHub has seen a huge increase in users, up from just under 1 million in 2012 to 3.4 million last year. But one way the company could see better sales is with some more cold weather.