All you need is some glue, sand paper, and two styrofoam rings.
K'nex builder Austron claims to have built the world's largest Knex ball machine, and we don't know if anyone would debate him on that. Stored at The Works Museum in Bloomington, Minnesota, the colossal structure stands over 23 feet tall and is made from over 100,000 pieces. It is said that it takes over 3 and a half minutes for a ball to climb to the top of the impressive toy tower.
Toy company, Goldie Blox, creates toys for girls that are outside the normal pretty-in-pink conception of what is appropriate for them. Their latest ad includes an extensive Rube Goldberg machine made out of traditional girls' toys set to a revised version of the Beastie Boys' Girls.