iphonethememaker.com is an interesting iPhone Theme Creation site, which lets you design your own iphone theme.
You can choose your favorite icons, desktop wallpaper, status bar, dock, etc. You can either upload your own pictures, wallpapers, icons from collection or choose from the existing gallery. It lets you preview the theme as your building. Once you’re done customizing the theme, click on the Compile theme button to create your theme. You can download a zip file and distribute or the site provides you an URL for download too. Pretty cool… try it here.