If you’re like Dr. Sheldon Cooper, you spend a lot of time working in front of a whiteboard. If you hate finding yourself with a thought but no board upon which to expand your thoughts, you’ll want to check out the Noteboard Foldable Pocket Whiteboard from ThinkGeek. When folded, it has the same footprint as a stack of 3 X 5 index cards, and it unfolds to 15″ X 27″. Both sides are writable, with one side plain and the other printed with square-inch and square-centimeter grids. It comes with a dry-erase pen and a case that can double as an eraser for the board. It’s $9.99 at ThinkGeek.