TiddlyWiki is a wonderful application to keep track of all kind of information, ideas, todo's etc. It's one I use daily, since many years, as well in my professional life as in my private life.
There are a few things that make TiddlyWiki unique from my perspective.
Then it has a flexible set of tags that can be applied to each "tiddler", which is the name for the unit of information in tiddlywiki. "tiddler" can refer each other, can include each other, can have custom-fields, you name it. Sounds complex and overwhelming at first sight, but actually once you have the hang of it after a couple of days use, this is really extremely powerful. Obviously search capabilities are included as well.
Finally, it also has extreme configurability options so you can tune appearance and behaviour completely to your own taste.
But I tend to run it pretty much run-of-the-mill and it serves me extremely well. In my professional life I start even to be associated with my tiddlywiki now storing years of experience.
Ah, one more thing, my development of cb_thunderlink is very much driven by it's use within my wiki's (connecting "tiddlers" of knowledge with the associated emails).
Go and have a look at https://tiddlywiki.com/