I use git-annex to:

• manage my research data, partly also with DataLad
• sync and backup personal documents
• sync media files to and from my SailfishOS phone
• sync, organise and backup a huge media collection
• experiment doing inventory management

I made a Thunar plugin for git-annex, here's a 📹 screencast.

In an attempt to #gitAnnexAllTheThings, I used git annex as a backend for a cli time tracker annextimelog. It has similarities with timewarrior but adresses many of its inconveniences. I talked about it a bit at my distribits 2024 talk, of which there is a recording 📹 on YouTube.

At the Tübix 2023 I gave a git annex workshop, of which you can find a recording of the initial talk 📹 here (🇩🇪 German) or 📹 here (English) in the fediverse and 📹 here on Odysee (🇩🇪 German).