Diego Inácio has created several geometry tools for Houdini, using Python.
Arnold for Houdini
Solid Angle have released the first public release of their Arnold renderer for Houdini.
Jayden Paterson - Houdini FX Reel 2014
Jayden Peterson has posted a reel showcasing his Houdini FX work.
De Planeta is an animated short by Leonardo Cavaletti that revolves around the birth, life and death of a little planet.