Digital artist Nathaniel Reeves has released NKS5: a very cool free collection of natural media and texturing tools for Photoshop CS5 and above.
(Actually, it came out last week, so a tip of the hat to Max Underground for spotting it.)
NKS5 includes one-click options for simulating natural surfaces such as sketchbooks, notepaper, graph paper and hardboard; a single toolbox of digital pens, pencils and markers, and a realistic watercolour brush.
The toolset also groups sharper, vignette and grime options into a single palette to add ‘grit’ to textures. There are quite a few other useful features, too: you can see them in the demo video above.
NKS5 is a free download, but if you donate, you get early access to future updates.
Read a full feature list for NKS5 (Includes download link)