MagicaVoxel - A free lightweight GPU-based voxel art editor and interactive path tracing renderer.
ChalkMotion - Create animated doodle slideshows
Goxel - Goxel is a simple, but powerful voxel graphic editor with 24-bit color support, unlimited scene...
Iceberger - Draw an iceberg and see how it will float
Cubik Studio - Model in a unique cubic style. Start modelization with boxes. Move, rotate and scale cuboids.
Sketch This - Daily drawing challenges