Crossover: The three inches of cushion and integrated foot pump and pillow on Nemo’s 1.8-pound Cosmo Air are pretty decadent. The one-inch-thick foam pillowtop cushion? Heavens to Betsy!

Rhode Island School of Design student Cam Brensinger came up with the idea for NEMO (New England Mountain Equipment) and his college senior project, high on the flanks of New Hampshire's Mount ...