Griffin and Threadless have teamed up to offer an awesome competition for artistic iPhone fans. The “Griffin iPhone 4 Case Design Challenge” is offering a variety of prizes – including $1,000 in cash – for anyone who can design an impressive iPhone case.

If voters rank your case as being one of the best, you could win $1,000 (in cash), a $250 Threadless gift certificate, $250 towards a Griffin “virtual shopping spree” or “your choice of an iPhone or iPad.” Furthermore, several winning designs will be available to purchase from Threadless, Griffin or Apple.

Sounds good, right? All the information you need can be found over at the competition’s webpage. There, you can submit your own design or vote for others. Here’s the submission webpage, and here are the guidelines.

Now hurry – you only have eight days left to submit a winning design! Good luck, and be sure to let us know if you’ve entered the competition in the comments.