Currently I’m using Joplin with Syncthing-backed file system synchronization. I’m pretty pleased with it, as I do like tagging- and Markdown-based systems.
I plan to upgrade to server-based synchronization, but before doing that, however, I wanted to see what other people are using.
Edit: So far I see a slight favor towards Joplin and Logseq, but I totally didn’t expect (and appreciate) getting so many different answers.
Joplin as well, syching my 3 devices with the WebDAV option. I checked a few other options about a year ago and Joplin seemed the best.
Joplin is where I landed, as well as hosting my own Joplin Server.
If Obsidian allowed a free self hosted option, I would have picked it over Joplin. (Yes, I tried the free plugin, but it at times wouldn’t sync correctly and I would end up losing notes.)