Diego Inácio has created several geometry tools for Houdini, using Python.
Houdini for Games - Frima Studio
See how Frima Studio use Houdini to generate content for their games.
SideFX have announced Houdini Engine, an API that will facilitate Houdini integration into proprietary studio software.
Nuaghty Dog Turn to Houdini for Uncharted 3
Find out about how Naughty Dog made use of Houdini for geometry fracturing and water effects in Uncharted 3.