To create your own instant workspace anywhere, put a flat birch hollow-core door atop two adjustable sawhorses.
Cover the door with self-healing vinyl board cover (available from art and drafting supply stores). The closer you can get the board cover to the exact size of your door, the better.
Stencil a basic measuring system onto the board cover, and you'll never need to hunt down a measuring stick.
Time: Four hours plus drying time
Cost: About $175