https://www.indxd.ink/
A digital, web-based index tool for your analog notebooks. Ostensibly allows one to digitally index their paper notebooks (page numbers optional).
It emails you weekly text updates, so you've got a back up of your data if the site/service disappears.
This could potentially be used by those who have analog zettelkasten practices, but want the digital search and some back up of their system.
<small><cite class='h-cite via'>ᔥ <span class='p-author h-card'>sgtstretch </span> in @Gaby @pimoore so a good friend of mine makes [INDXD](https://www.indxd.ink/) which is for indexing analog notebooks and being able to find things. I don't personally use it, but I know @patrickrhone has written about it before. (<time class='dt-published'>10/27/2022 17:59:32</time>)</cite></small>