Those notes are dropped into a pretty, lidded box, big enough to let notebook paper lie flat. Every week or so I incorporate, reviewing at the same time, the loose notes into the computer notes. Ten or so years from now, this can all be formatted and printed out in a pretty font on pretty paper to make An Attractive Learning Journal. Obssessing over where I left which notebook uses up my limited study time. I also keep a separate topical quotations file much in the manner of Jane Austen's Little Advice Book.
Words are so neat and there are such geniuses out there.
Please keep the ideas coming. Consequently I have notes everywhere, written on everything, including important phone numbers penciled inside my un-loseable cabinet door. About half of my serious study is noted at the computer and the other half is done during waiting times at many locations. If I'm lucky, I have my zippered loose-leaf notebook with me. If not, I write on anything available.