I decided early this year that exercising in the cold was not going to happen. So I have been walking the isles at Walmart. I don't know if it's because I don't have a cart or maybe because I am walking briskly, but I often get mistaken for an employee.
I helped a woman find some duct tape, I got a can of roast beef off the top shelf for some guy and helped some woman pick out the paint color for her bathroom. :)
BTW I estimate 20 min at a brisk walk = 1 mile.