One item that I have is a homemade memory card holder. It holds 3 overlapping CF cards in their plastic containers and slips easily into small pockets on the straps of one of my packs. It was made as an experiment, so has been done by crocheting. The plastic container for the CF card was used as a mould. It's naturally stretchy, and easy to handle.
I recently discovered the Cocoon Grid-It system. I recently assembled a connector kit for audio and used it along with a Think Tank Cable Management 20 and a 15' mini to mini cable. I'm giddier about this than I should be.
Oh, that looks supersmart and useful in so many ways! I even think it would be possible to create something similar from scratch to fit inside pockets of my backpacks. *scratches head and starts thinking*