Ben Barrett-Forrest created The Design Deck, a nifty set of playing cards that each have facts about graphic design on them.
Each of the 52 faces contains a useful piece of information about graphic design, including typography, colour theory, design techniques, history, and more, with beautiful visual examples. Printed in rich, full colour on high-quality Bicycle® stock with air-cushion finish.
This started off as a Kickstarter and grew from there:
There's also The Font Deck, a set about fonts at the site below.