Zibby, you are so right! Both my kids played with the Discovery Toys Marbleworks for years. They used the marbles, along with sand, water, little cars, dry pinto beans, pebbles-their imagination was the limit. They reconfigured it every which way too.
No batteries, no noise, no directions. It was their favorite toy up to 8, 9 years old.
You can still buy it online, and yes, it is pricey, but lasts forever. I really wish I had kept it for my grandkids, instead of selling it on Ebay years ago;(
Marbleworks--powered by CREATIVITY!