Great idea. I found this on Aliexpress. https://nostr.build/i/nostr.build_f56c0049b2efd5e11d956609c644ecd77a76552c14a53a7c5ea8145cc5bbc8e3.jpeg

there are a number of products that are like otg / lightning storage that also work as chargers, sandisk ixpand is the name brand one, isn’t very cabley, some Amazon knock offs are a bit more cably but like 6 inch. Could always put an ultra fit in fresh housing, solder the cable to the housing t...

There are a few tutorials on how to make one but nothing I could find to buy ready made. https://www.instructables.com/Secret-Flash-Drive-inside-an-USB-cable/

Actually, I had another look and just found these. any good? https://shop.hak5.org/products/omg-cable https://hackerwarehouse.com/product/usb-ninja-cable/ https://uk.pcmag.com/news/119592/evil-usb-cable-can-remotely-accept-commands-from-hacker https://counterespionage.com/malicious-usb-cables/