If you do not want to run around with an off the shelf Apple iPhone there are many ways to personalize yours. The expensive option is to have it plated with gold or coated with diamonds, but there are also crystal cases that are easy on your budget and also protect your iPhone.

USB Fever offers this white crystal case that has a very cute puppy photo printed on the back.
This iPhone cover sells for $16.99 on USB Fever.

But a definite no go is this iPhone case.