Curiosity question: once you've posted the note/info to one of your digital capture points, why keep the 3x5 card?
Fair question. It's basically that it takes just a few seconds to file them and I feel safer having all of those quick notes in one place. On the rare occasion that I can't find something a note on my computer, I almost always remember the topic of the note and have it as backup. I generally toss them after a year, though, and start fresh.