MyPhotoshopBrushes is a great collection of Adobe Photoshop brushes, patterns, tutorials and many useful Photoshop stuff. They are made by artists all over the world and all are free to use. Take a look, find something interesting for you, download it free and use them where ever you want.
If you want to share your Adobe Photoshop brushes, patterns, styles, gradients or custom shapes you can also submit it on the list.