A long time ago, back when the internet boom was still a gleam in its geek's father's eyes, Shay and Rob went to help get etoys.com off of the ground. In the course of their work, their favorite test search string was 'Big Balls'. Partly because it's a fun thing to type into a search widget, but also because the main result was this really cool Knex set which was called 'The Big Balls Factory'.
As a thank you for their work, etoys got them one of these that we put together one night in the Caltech dorms. It was a tun of fun to build this huge (5 foot) structure and eat cheesy poofs and just get geeky with construction toys.
Anyway, they've apparently made a new version of the Big Balls Factory with some different cool things for the balls to do on the way down. And since Toys R' Us seems to have it on sale right now, I picked one up and spent last night putting it together.