REI Garage offers the JanSport Onyx Equinox 34-Liter 15" Laptop Backpack in Black for $54.73 with free shipping. That's the lowest price we could find by $23, excluding the below mentions. It features a padded sleeve with back zip access that accommodates laptops up to 15" or a 3-liter hydration reservoir (reservoir not included), tricot-lined padded tablet pocket, multiple exterior pockets (including a tricot-lined sunglasses pocket), organizer panel, perforated adjustable shoulder straps, corrugated back panel, tuck-away hip belt and sternum strap, and side and bottom compression straps.

A couple of close prices: Backcountry offers it for $54.97 with free 2-day shipping, and 6pm charges $55 with free shipping.