Do you not have an insulated coffee flask yet? Do yourself a favor and pick up the Primus Vacuum Bottle. This sleek double-walled bullet holds one liter of your favorite wake-up concoction, lunchtime minestrone, or post-ski-tour cider laced with liquid courage. It won't spill, the top functions as a cup, and it keeps hot liquids hot for a loooooong time. We take ours everywhere.