Neo Textures is a free and open source software that uses nodes and procedural data to create tillable image textures and displacement maps.
Ranked in these QuestionsQuestion Ranking
Pro Powerful control on procedural nodes
Can easily modify all of the multipliers and alligorithm values of procedural generation.
Pro Faster than Substance Designer
Neo Textures editor is a free and open source project available on SourceForge.
Con No longer being developed
Neo Textures is no longer being developed. The project seems to be abandoned.
Con Doesn't support PBR
Neo Textures was created before PBR was a thing, and it's based on the deprecated Diffuse/Specular rendering pipeline, which is no longer used.