There are free textures, brushes, custom shapes, and other resources on the web for Photoshop to enable a web designer/developer to be more creative in website design. I have just begun collecting some of them and offering them on my site. I will offer more as time allows.

Filters

• Download MuRa's Seamless
  A Photoshop filter that makes any image seamless. Great for seamless backgrounds.
  
• Download MuRa's Clouds
  A Photoshop filter that makes seamless clouds and cloud effects on an image
• Download MuRa's Copies
  A Photoshop filter that makes many copies of the image and pastes them on it.
• Download MuRa's Pole Transform
  A Photoshop filter that transforms an image to polar coordinates or rectangular.

Textures

• Download Mayang Textures
  Beautiful unaltered textures taken from their own camera. Very useful!
• Download Ken's Textures
  Extremely creative and artistic textures. Very nicely done by Ken's Graphics.

Plugins

• ICO Format
  This plugin gives Photoshop the ability to directly Open and Save Windows icon (.ICO) files.

Click here for other great sites that offer Photoshop resources. Most of these resources are free and others are at very little cost. I will add more resources as time allows.