One huge vault! Handles all my:

• Notes about clients for my work
• Dungeon master plots and notes
• Jokes
• Articles/books I’m writing
• Funny life stories I want to remember
• Recipes
• Vision boards for decorating/gardening
• Notes about books I’ve read
• Dream journal
• Therapy Journal
• Facts to remember: earring gauges, door codes for work, id numbers, etc

I use syncthing to keep them synced between phone and desktop. But realistically I only ever really use the phone

3 Vaults:

• my personal vault with daily notes, book notes, recipes, notes about current special interests
• work notes with cli commands, code snippets, project notes
• a shared vault with my husband with notes about travel plans and shared hobbies

Seven. One is for my personal notes. The other 6 is for various TTRPG campaigns.

One per universe. Of course I play ttrpgs.

One. University, organizing my life and work.

3 at the moment.

• Work notes
• D&D Games
• My hobbies and whatnot

One vault keeps my list of games to play, things to read, etc. for later. I have it set up a particular way for quick and easy entry with the Meta Bind plugin, and DataView for easy listing of everything (each piece of media to consume is a separate note with tags according to things like genre, subject matter, etc. and DataView sorts on those). This gets a whole vault to itself because of how every piece of media is a separate note: not much information in one one; when I usually have one note with a lot of stuff in it. This would absolutely clog any other vault. It also gets a whole vault to itself because I have no need for DataView or Meta Bind at the moment in my other vaults. My other vaults are plugin-free.

I also have a vault for storing notes on my personal creative projects, whether it be a long-abandoned attempt at planning a TTRPG campaign or a video game.

One for academic notes. I also have a separate math vault that did not end up getting very far, intended to help me review a bunch of math I already learned (and maybe to one day share to help teach others), maybe I’ll pick it up again.

Finally, I have a sort of catch-all vault for everything else in my life I might want in Obsidian. This is my most frequently used. It’s where my recipes live, where information about myself I should probably know about myself but often forget lives (like the exact day I moved into a different house), where I keep track of knitting patterns and my progress on them…

This is not how you are “supposed” to do it, I always see advice to keep everything in one vault, but this is what works for me.

Thanks for posting this question!

I’ve had a few. I have one to sync with my Pocket notes that I give tags. I use one for my general notes. I’ve used one as a research space for a podcast, and I plan to start one soon to do world building for my TTRPG and fiction settings