Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Mandelbulber - A 3D fractal renderer.
MakeHuman - MakeHuman is a free, open source, interactive modeling tool for creating custom 3D human characters.
TouchDesigner - TouchDesigner is a visual development platform that equips you with the tools you need to create stunning realtime projects and rich user experiences.
Bforartists - Bforartists is a fork of Blender.
Structure Synth - Structure Synth is a tool for creating 3D structures from a set of user specified rules.