J’adore these iPhone 4 cases by Dannijo. Never underestimate Dannijo to only be good at jewelry. These cases are sold for $95 and can be found on Shopbop.
If you want to pick your own photograph to put on your iPhone case you can use this great website I found http://www.giantsparrows.co.uk/. It is based in the UK but they ship all around the world. You can choose artwork that is featured on their website or upload your own image and they make your one of a kind case and then ship it to you.
Today it seems everyone and their dog has an iPhone so you might as well try and be somewhat original by decorating it differently than with a Speck case.