Homemade Magic Erasers recipe?

A while ago, I went through some MSDS sheets and other information to figure out how to make your own windshield washer fluid. Inspired by Dan's comment on Mr. Clean's Magic Erasers, I thought I'd do a bit of digging, not only to see if they contain formaldehyde, but to figure out what they actually are. The Magic Eraser MSDS sheet does state that they don't contain formaldehyde (my attempt at degreasing car parts with them might have been more successful if they did!), but it doesn't state what they actually do contain. A bit more searching, though, turned up that Mr. Clean didn't really try to hide their source for the Magic Eraser material - it's actually melamine foam, made by BASF.

Normally, melamine foam is used as a sound insulation, although it's also used as a fire retardant. At some point, somebody found out that if you cut this sound insulation foam into blocks, you could use it as a very fine grit abrasive. So the way a Magic Eraser cleans is mechanical, not chemical - it's like a polishing cloth or sandpaper. And, predictably, a little searching for "melamine foam" turns up a couple sources where you can buy the stuff cut into blocks for sound insulation use. Predictably, McMaster-Carr sells it. (If that link's broken, start at their main page and search for melamine.) It's worth noting this is a different grade of melamine foam from what Mr. Clean uses, and it would only make sense if you used Magic Erasers by the crate.