Many creative types like pen and paper versus design software when designing the UI for that new killer app. The folks at Design Commission understand this and have come up with an excellent set of tools to add to your box.
The iPhone Stencil Kit is an iPhone sized stainless steel stencil with all the UI controls you could ask for. They include sliders, playback controls, icons, buttons, dialog box, and stars. When you purchase the stencil kit you also get a Zebra mechanical pencil and a downloadable .PDF letter or A4 sized printable template of an iPhone.
To compliment the stencil kit, Design Commission has created the iPhone Sketch Pad. Each sheet has one iPhone silhouette on the front side and three on the back, for a total of 200 possible screens per pad. The pad is 8.5×11 and is made with 50lb paper. There are grid lines, project name, screen and date fields as well.
Sketchpad is Price: $7.95