Tech-savvy stoners are going to love the iHit iPhone 4 case. The iHit is a case designed to protect your iPhone 4 and let you discretely transport a "one-hitter." A one-hitter is a small smoking device used to take one hit of tobacco or (more likely) marijuana.
The iHit iPhone 4 case is made out of rubber and features a small pouch on its side that is the perfect size for hiding a one-hitter. The iHit would definitely appeal to smokers trying to secret their stash, but I can't really see it appealing to others as the added pouch increases the width of your iPhone 4 and makes it look less like an awesome piece of tech and more like a touchscreen brick. The makers of the iHit are currently seeking funding on Kickstarter to help pay for supplies and put the case into production. You can check out a demo video for the iHit as well as a few conceptual images here.