Ucon Acrobatics' new Lotus Series Adan Backpack might be exactly what you're looking for if you've been seeking out a bag that delivers serious functionality while flying under the radar with a minimalist aesthetic. The sleek and virtually brand-less exterior is made out of a rubberized, rugged and waterproof polyurethane-coated fabric and it has up to 19L of capacity when unfolded and 16L when folded. The rolltop closure is secured by strong magnets and a discrete padded rear zippered pocket has enough room for a 15.4" laptop. 

€129 (approx. $144), ucon-acrobatics.com