In 1969, Apollo Eleven'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 spaceship. Astronauts and homeowners have the same problem, whether strolling around tranquility base or just coming in from the backyard. To solve it, make a boot scraper by digging a foot-square hole near your door. Fill it with concrete and sink a shovel into it six inches deep. When it dries you will have a permanent boot scraper, with a handle you can hold onto for balance. For added cleaning, place a sturdy scrub brush, upside-down, with bristles up, in the wet cement, too. And that's the On The House tip for today.