QRazy.fun rocks you with a crazy way to tag everything with a tiny QR code that attaches a paragraph or two of text. I find QRazy.fun ("crazy fun"— the dot is silent) to be useful for things like thumb drives where the content isn't obvious, they might get repurposed from time to time, and there's not enough room for a comprehensive label. I also use them to identify items in my refrigerator or freezer (the timestamps help keep me from poisoning myself), boxes and crates I put on shelves, devices that need additional information (here's an example), old photographs that need a lengthy description, and many other things.
You will need labels to have QRazy.fun, so follow the printing instructions and print some.
A limited number of tags are available for free. Acquire your tags and a Secret. I don't know if I will be able to keep tags free forever, but the cost (if any) will always be low. Once you create a tag, you should be able to access it for free as long as QRazy.fun exists.
Once you have labels and a Secret, just stick a label on anything that needs a tag with more information, scan the label, and create the tag.
iOS (iPhone) and Android phones can scan QR codes using the built-in camera function. There's no app to install, no 38-page contract to which you must "Agree." If you want to scan a label from a webcam-equipped desktop or laptop, you can use the webqr.com web site.
QRazy.fun is a hobby project. It comes without any guarantees. I have a pretty good track record -- I've been running my own servers since 1999 -- but I could give up at any moment. Use QRazy.fun all you want, but don't depend on it for anything critical.