Fingerprint- and germ-covered Lego bricks can be washed successfully in the washing machine if you leave out the ones with stickers or paint. Fill up a pillowcase with the bricks, and tie it tightly so that none escape. Then, wash on a cool-water cycle with other clothing. Do not put them through the dryer, of course, or they could melt. Instead, let them air-dry on a towel, and then invite some buddies over to sort them.