We blogged about Protomold a couple of years back; they're a Minneapolis-based company that does quick turn-around injection-molded plastic sample parts by rapidly building soft tooling from a client's CAD database to get actual molded parts shot in a matter of days. What we didn't realize (until now), is that shortly after that posting, they came up with one of the coolest gimme trinkets we've yet to see: The Protomold Cube.

Described by one friend as "an ME degree in a box," the Cube is a single molded piece that folds into cube shape, and features physical examples of over a dozen guidelines of good injection-molded part design: there are snap fits, pass-core features, live hinges, ribs, knit lines, textured surfaces, and several examples of how to design and not design a boss to minimize sink. Best of all, it's free through the Protomold website to anyone who can convince them they're a bona fide designer or engineer. If they'd handed these out on the first day of Production Methods class, we could've slept in for the entire semester.