One of the coolest features of the iPhone 2.0 software is the ability to save images from the web to your photos. Didn't realize you could? Just press and hold your finger on one of the following images, and you'll be given the option to save the photo. These wallpapers are from the iPhone Wallpapers group on Flickr, and are formatted to perfectly fit your iPhone.
Patterns and Textures
Don't forget - you can add these to your iPhone from this page. All you need to do is hold your finger on one of the wallpapers, and your iPhone will pop up a window allowing you to save the image to your photos. Namaste!
Beginning iPhone 3 Development: Exploring the iPhone SDK
The iPhone Developer's Cookbook: Building Applications with the iPhone 3.0 SDK (2nd Edition)
Wallpaper City Guide Barcelona 2011