I have an org-mode file open in Emacs pretty much all the time that I can write stuff down in. Emacs used to have a reputation for being bloated and resource intensive but it's one of the lightest tools that I use these days and I just have it sat there in the background.
I keep hearing things about emacs org mode that sounds awesome but I am afraid how much of a time-sink it would be to switch from my current process. I currently write all of my notes in markdown and in vim.
I used to think like that, but org files can be exported to pretty much anything (including markdown). I write my blog posts[0] in org then export them in markdown just fine. I use Vim (well, Neovim) solely for coding.
0: rmpr.xyz