This can question can be broken down into 2 parts.

1. On the server side of things - how do I make for example '1.jpg' a random image? (I have read a few things on the internet which show how to select a random image using PHP and display it on your web site e.g. A List Apart: Articles: Random Image Rotation but this is not exactly what I want. I want to OVERWRITE 1.jpg with a random image on a daily basis.. Is this possible?
2. On the client side of things, is there SOME way of automating the selection of the users wallpaper from a web page - as far as I know there is not, so I would have to give them instructions on how to go into 'Display Properties', 'Desktop', 'Browse', type in the web address of the picture etc.

OR is there any way to use RSS to automate this process?

NB - comments on how to do this with Apples also welcome!

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Irish Wallpaper/Photos/Desktop Backgrounds|PPC NI| Google Advertising Professional