I throw every random information in an Evernote notebook. For more complex stuff, like what are my priorities this month, I draw a mindmap using MindNode. Also, I've got in a habit of reviewing all my important notes and trim them every month.
Finally, I put all the interesting web articles in Pocket, because I search them later.
I tried to make flashcards in Anki for random stuff, but it didn't work out.