To be fair, I'm usually travelling at least one leg on Norwegian where the free bag is smaller, work is never paying and I'm usually gone for longer than a week. I've got a fairly focused set of things that I always keep in the bag, but a USB cable has recently dropped out as it wasn't proving to be much use.If I'm travelling for work, for up to a week, I use a 25L backpack which is too long for the Easyjet/Ryanair rules for a free bag. I'm on expenses, so I pay for it as a cabin bag, but I still keep it in the footwell rather than an overhead locker.
The two 10cm USB cables and a USB A to C adaptor fit into a 9cm * 5cm * 3cm case with a folding pair of reading glasses.
I use one of these cable organisers (20.3cm * 12.9cm * 7.2cm), for the 130W and 45W USB chargers, european plug adaptor, alarm clock, mouse, USB C adaptor with various ports, USB thumb drive, spare ear bud headphones, pen, sewing kit, two 4cm long screwdrivers, safety pin etc.
The mains lead for the laptop fits in the case for my headset. I'll then have a 15" laptop and a 12" Chromebook, toiletries and some clothes.
It's a bit paranoid for my tastes, but worth noting that using random USB cables and chargers is a rapidly-growing security risk.
