I don't design websites very often (I've done maybe five or six total), but whenever I do, the first thing I do isn't anywhere near the web: I grab a pad of paper and a pencil and sit down somewhere away from the computer to sketch out my ideas for how the design will go.
Lots of developers will do the same thing with applications, and so, to help those developers, the folks at Labs.Boulevart were kind enough to put together sketchpaper versions of the iPhone. It's a free download (in PDF or Photoshop flavors) of just a bunch of images of the iPhone, left completely blank (sometimes with the MobileSafari and/or carrier bar on there) for designers of all kinds to sketch on and imagine with as they will.
Very cool idea, and the number of different setups and implementations they've thought of is impressive -- just the kind of thing to get the iPhone creative development juices flowing. If you're doing any kind of design for iPhone applications, native or on the web, this should be a cool tool to use.