Inspired by: https://www.instructables.com/id/Laptop-Sleeve-made-out-of-some-used-military-fabri/
I took my dad's old 1960s Boy Scout backpack, removed the pockets and frame, cut the bag apart, lined it with a soft blanket (that I took off an airline flight), and sewed it back together. Sewing a pocket back onto the front made a pouch for my laptop charger. I took the two shoulder straps and sewed the two ends together to make a nice long shoulder strap. Make sure you leave some grommets at the top for the strap to hook onto.