Scrub Daddy: smiley sponge that firms up in cold water — from 3M 'scrap' to a $220M brand

Aaron Krause built a car-washing and detailing business out of college and invented a buffing pad for polishing cars. In 2008 he sold that company to 3M — but the sponge he had designed as a hand scrubber for mechanics was carved out of the deal. 'They left it with me because it was so worthless,' Krause recalled; the yellow sponge sat in a box labeled 'scrap' for three years.

In 2011 his wife asked him to clean moldy lawn furniture. Krause found the rejected sponge, tried it, and watched the grimy chairs come up sparkling clean. He invested $150,000 to patent it, rebranded it as a kitchen sponge called Scrub Daddy, and began demonstrating it with hot and cold water in a friend's Philadelphia grocery chain: sales went from 2–3 sponges a day to 200–300 in one store. QVC airings sold out, and in October 2012 he took the pitch to Shark Tank.

The episode set off a bidding war among the Sharks, and Lori Greiner won with $200,000 for 20%. Sales crossed $1 million within 24 hours of airing. CNBC put cumulative sales at more than $110 million by 2017 and $209 million by September 2019; Fortune reported $220 million in 2023. A sponge 3M had written off as worthless had become one of the most successful products in the show's history.