For a long time I have been looking for the ideal solution to easily record and retrieve ideas.
Sketchbooks, random pieces of papers and napkins are great for sketching and writing down ideas ... but it's not the best medium to recall and ideas. I can never remember which sketchbook a specific idea was in and over the years this only gets more complicated. There isn't really a good way to organize these ideas in the physical world even if you try to categorize these ideas in folders. (I will explain below)
The digital medium has the opposite problem .. it's great for retrieving ideas through search, browsing, tagging, etc ... but isn't so great for recording ideas. Ideas happen spontaneously and a lot of the time when you have an idea, all that is available to remember it is a napkin, a piece of paper .. or maybe a sketchbook. I have tried PDA's ... but they seem to be limited for one reason or another and some don't have sketching capabilities. Half the time when I have an idea I don't have the PDA with me, it's out of batteries or it's too much of a pain to input a complex idea with diagram, notes, etc .. and pen and paper is much easier, fluid and spontaneous..
digi-LOG - So here is a great free solution ... EVERNOTE
Here is a DEMO of how it works.
update: Evernote is a better solution because it syncronizes over all platforms (ipod, blackberry, computer and web)
For more ideas that are intended to help illustrators check out: