Anyone else on /bant/ do creative things as a pass time, or even a job?

I want a programme that allows me to brainstorm really easily, something that can efficiently create detailed flowcharts with potentially hundreds of off-shoots and stages. Free would be nice, since I'm paranoid about the internet having my details (yeah, I'm that autistic)

I remember one from school where you could start with a thick line that would then split into threads as you clicked on it, that you could write ideas on or label. Idk what the program was, but it definitely wasn't anything Microsoft
Does banter know anything like that?

Also ITT general discussion of creative things