Diego Inácio has created several geometry tools for Houdini, using Python.
Point Render for Houdini
Point Render is an extension for Houdini that expands 3D rendering for computing scenes with full freedom of artistic effects.
Houdini Demo Reel 2015
Side Effects Software have posted their demo reel for 2015, featuring the work of Houdini customers worldwide.
Arnold for Houdini
Solid Angle have released the first public release of their Arnold renderer for Houdini.