Woot offers SwissGear 3598 Backpack Narrow Daypack for $19.99 free shipping with Prime. 

Product Description:
Crafted specifically for the urban commuter, the narrow SwissGear 3598 City Backpack has a deceptively spacious silhouette with an extremely low profile that is highly unobstructive on one’s back. With a front organizer panel and a designated tablet pocket, secure your devices and effortlessly retrieve them at the office or airport. Ergonomic shoulder straps and back Airflow panels accentuate its built-in comfort.