I recently purchased a new rucksack.
Yes, another one.
Some people buy shoes, or clothes, or purses, or gadgets, or games. I buy rucksacks.
Because of my RA I can't carry regular bags easily and shoulder-bags pretty much kill me. No joke, I seriously ended up at the ER once (with Christmas) because I carried one and it gave me horrible tendinitis that left me in so much pain someone had to drive me to the hospital. I easily get tendinitis in shoulders and neck, and a rucksack seems to work best in preventing it.
This one weighs less than a kilogram on its own, has its own rain-cover and it came with a separate pouch you can either hang on that loop on the inside, or attach to the waist-belt.
Bonus-points if you guess who I have hanging on it. *[RA]: Rheumatoid Arthritis