Sierra Designs Backcountry Bed
For the most part, we haven't seen much change in the basic idea of what a sleeping bag should be — an insulated tube with a side zipper — but the Sierra Designs Backcountry Bed changes things in a big way. Completely doing away with the side zip (or any zipper for that matter), this bag opts instead for a comforter-like blanket covering an oval-shaped opening at the top of the bag. This design lets you slide in comfortably, while using the comforter to hold in your body heat, or moving it for ventilation. Coupled with polymer treated 600-fill down that resists moisture ten times longer than typical down, and what you get is a versatile alternative for comfortable sleeping that pushes the envelope more than anything since the mummy.