Many of us use daybags for out daily outings. Some use their personal item. Others use a packable backpack.
My personal item is too large to use as a daypack. (No, I can't take a smaller one.) I needed to find something small.
I have a few packable one but even they took up too much space.
Then I found the Nanobag Daypack.
It weighs just over an ounce, can hold up to 66 pounds, and folds up into practically nothing. I wouldn't use it for a hike into the woods, but to carry the basics while sightseeing, it does the job.
I also have one of their Nanobag Standard Totes to use as a shopping bag. It's about the same size and weight as the daypack and can hold a surprising amount.