The Free Universal Construction Kit

Here is a reason why I want to build a 3D printer (I am just waiting for the one I want to be available [Printrbot]), I want to build things like The Free Universal Construction Kit.

Below is except from the site, "Ever wanted to connect your Legos and Tinkertoys together? Now you can - and much more. Announcing the Free Universal Construction Kit: a set of adapters for complete interoperability between 10 popular construction toys."