Stencils and Sketch Books
Going beyond the whiteboard.We get many things from whiteboards. One of those is a sense of impermanence - that the work on them is a work in progress. That it's a sketch, rather than a final product. And I missed whiteboards, so working with my partners at Agile Stationery, we created not only whiteboards, but also stencils to help you neaten up your threat models as you iterate through them.
And here's a random tidbit of "products are hard" for you: we started out with the ruler in centimeters (hey, you're an engineer!) but the books were already printed with 1/4" grid (didn't think it through). So the final production stencils have an inch-denominated ruler.
If you have other geeky ideas for the next rev of the stencil, let us know!