Diego Inácio has created several geometry tools for Houdini, using Python.
Making of Ambition with Houdini
Platige Image go behind the scenes on their Ambition short film and how they used Houdini for the effects.
Houdini Indie and Houdini Engine Indie on Unity Asset Store
Side Effects Software have announced the availability of Houdini Indie and Houdini Engine Indie on the Unity Asset Store.
Houdini Engine for Autodesk Maya
SideFX have released Houdini Engine for Maya, with 3ds Max and Unreal versions coming soon.