Call me cheap, but I hate the design of the rubber sanding block, mostly because I can't stand that one-third of each sandpaper strip is wasted in the ends that you have to tuck into the spikes. I save the little perforated, untouched bits but never get around to using them.
A product currently under consideration at Quirky looks to replace the sanding block—and the sandpaper—entirely. Sandables are essentially moldable, elastic, claylike objects embedded with grit.
"The sanders are pre-shaped for maximum utility," writes the site, "but 3 minutes in the microwave allows each to be molded to the desired shape, whether you're attaching a stick for added reach, or fitting a tight corner." After sanding formaldehyde-laminated plywood I probably wouldn't be willing to stick these in the same nuke I eat out of, but it looks like you can hit 'em with a heat gun too.
One thing I'd need to see before I commit are what grits they come in. Quirky mentions they'll have "three distinct grits," and while I could probably get away with 80, 120 and 220, I want to see which they've chosen as the essentials. I'd also like to hear how long they last for, or if you can blow the dust off of them with a compressor to keep them going indefinitely. And secondly, can they retain a flat shape, or do they start to deform?