Our pals over at JackThreads are selling a bunch of Karvt iPhone 4 wooden skins today at 40% off. The skins typically sell for $25, but JackThreads has them today for $13.99. Even better, you'll get a $5 credit put into your account when you sign up for JackThreads using our invite. Apply it to the skin, and the cost drops to $8.99. Not bad!