PixPlant - A complete solution for repeating textures and 3D maps. Save a lot of texturing time with PixPlant!
Material Maker - Cross-platform, procedural texture generation tool.
TexGraph - Node-based, procedural texture creation tool for Windows.
Substance Designer - Substance Designer is a node-based non-destructive application for material authoring.
Wicked Backgrounds - Create beautiful background waves
Filter Forge - On the surface, Filter Forge is just a Photoshop plugin, a pack of filters that generate textures...