I like to carry some knitting or crochet with me when I'm out & about. Usually I just throw some wool & needles into a small carrier bag. The Argos catalogue bags are favourites.
In my Christmas Stocking last year was a fat quarter of fabric and some ribbon.
I made a simple drawstring bag.
I put pockets inside for scissors & finished granny squares.
So simple to make. I can just throw it in my handbag or work bag and always have my crochet with me.