There is probably an interesting opportunity in this idea and many ways to execute it. There are also existing products trying to address the problem. DEVONthin

There is probably an interesting opportunity in this idea and many ways to execute it. There are also existing products trying to address the problem. DEVONthink and Scrivener come to mind - both seem to have customers, but they are not what my dream product in this area is... In my daily routine I use Moleskine with two colour pens where I put both textual notes and many sketches and diagrams. The act of noting down what I learn/think is helpful in remembering it, but I would love a digital version of such 'idea journal' with all the modern tagging, searching, indexing, filtering and editing digital options!