By far the best I’ve found is The Brain (
https://www.thebrain.com), a mind mapping software. Unfortunately the paid version is pricy, but I’ve found it’s worth it.
There are other mind mapping products out there, but they lack a key feature of the Brain and what, in my opinion, actually makes it a true mind mapping product.
You can create infinite links between all “thoughts.”
Here’s an example of how powerful it can be. Say you make a thought of a character - Bilbo Baggins. He is linked to the thought for Burglar, where you have the rules for the class. He’s also linked to the Fellowship of the Ring, the members of the Fellowship, Hobbiton, the Baggins family, the Ring, through the ring you get to Gollum, etc.
All of these links show up visually when you click on Bilbo, which becomes the center focus. If you click on Fellowship of the Ring, it becomes the focus, and you see all of the links from that.
You can search, of course, create color coded categories, and there are several types of links that describe their relationship (and you can create labeled types as well)
It totally blows a Wiki, OneNote, EverNote, or any RPG tool out of the water. Seriously, nothing comes close, and I’ve been looking.
