I collect all letters and notes I find in a "Barrel of Letters" and the sales receipts of my player vendor in another bag. Which makes me wonder - why do all ingame letters and notes have a weight of 0 (even multipage as e.g. the newsletter of the elfhater in Bloodriver Outskirts), but player crafted letters or player sales bills have a weight of 0,1? Would it not make more sense to either have them all have 0 weight or all 0,01 instead of some most 0 and some 0,1?