In 1969, Apollo 11's lunar module landed on the moon carrying two men. The hatch opened and Neil Armstrong became the first man to walk on the moon. Returning, he also became the first man to track lunar dust and moon crud into a space ship. Astronauts and homeowners have a common problem, whether caused by strolling around tranquility base or just coming in from the backyard. To solve the problem, make a boot scraper by digging a foot-square hole near your door. Fill it with concrete and sink a shovel six inches deep into it. When it dries you will have a permanent boot scraper, with a handle you can hold onto for balance. For an extra shoe-cleaning feature, add a sturdy scrub brush, upside-down (bristles up) in the wet cement. And that's the On The House tip for today.