Link roundup

1. The US Army design guide is available for download (top, right). Via.

2. "On Feb. 5, 1958, a B-47 bomber dropped a 7,000-pound nuclear bomb into the waters off Tybee Island, [Georgia], after it collided with another Air Force jet. Fifty years later, the bomb — which has unknown quantities of radioactive material — has never been found." Via these sites.

3. Custom Portal gun.