An extensive add-on for Photoshop for creating textures for 3d models which includes two tools: dDo is for creating a fully textured model using a massive material library to choose from. nDo is for creating normal maps intuitively with many ways to tweak and blend details together.
Ranked in these QuestionsQuestion Ranking
Pro Massive material library
You never have to download textures off the internet ever again as it comes with a very large material library to work with.
Pro You don't have to leave Photoshop
If you like Photoshop so much, Quixel Suite is for you as you never have to leave any tools behind.
Pro Ability to paint directly on 3d models
The included 3Do viewer allows you to both view and paint on your models so you don't have to guess where that one spot is within your UV unwrap. Note that this is limited to painting masks, you cannot project textures.
Con High hardware specs for smooth performance
This loads alot of texture data during typical use and comes with a fancy 3d viewer. If your hardware isn't up to spec, you will experience some major slowdowns when using it.
Con Doesn't always play nice with manually added layers
Quixel Suite basically takes over Photoshop in terms of layer creation and management. While you can still create layers manually, Quixel isn't always aware of it and may confuse the software.