One thing about us here at Kotaku, we love a 3D Games Design Tool with a happy Atmosphere. Or an Atmosphir - as in the case of this 3D platform game maker from Minor Studios. It's a closed beta at the moment (you can sign up through their site) but from the video (see below the jump) it looks like a cross between a Lego set and Mario 64-style platforming. The full package is due out 'by the end of the year'.