Not a physical product, of course, but a physible one, consisting of almost eighty free 3D models from anonymous designers at the Free Art and Technology collective :

The Free Universal Construction Kit offers adapters between Lego, Duplo, Fischertechnik, Gears! Gears! Gears!, K’Nex, Krinkles (Bristle Blocks), Lincoln Logs, Tinkertoys, Zome, and Zoob. Our adapters can be downloaded from and other sharing sites as a set of 3D models in .STL format, suitable for reproduction by personal manufacturing devices like the Makerbot (an inexpensive, open-source 3D printer).

I’d vote against the naughty acronym, personally, but they do thrive on controversy, those F.A.T. peeps.

The Free Universal Construction Kit

Lego bricks builders wish they could buy