This daypack is durable, weather-resistant, and has multiple compartments for storage. Right now, it's 40% off at Patagonia (but only while supplies last).

Patagonia's Black Hole line (which, in addition to daypacks, also includes duffel bags, tote-style packs, hip belts, and packing cubes) is known for its roomy main compartments, abrasion-resistant ...