The trenches are dug, and for the next two weeks McDonald’s and Tim Hortons will be in full combat mode. Yup, it’s Roll Up the Rim time. And this year Tim Horton’s arch-enemy is countering the hope of winning cars and other prizes with the ultimate give away: free coffee for two weeks. No purchase necessary. And since the chain has spent a lot of time and money upgrading its brew, this promo is undoubtedly giving execs at Tim Hortons a headache. Quick, better get a cuppa.