TomTop offers the Xiaomi Casual Backpack in Black or Blue for $29.99. Coupon code "MIBACK6" cuts that to $23.99. With free shipping, that's the lowest price we could find by $4. It fits a 16" laptop and features adjustable shoulder straps and a side water bottle pocket.

Note: The countdown timer on the product page does not reflect an actual expiration time and resets daily. Also, this item ships from China and requires two to five weeks for delivery.