Prototyping
I've been using Keynotopia and Invision to put together some clickable prototypes for an iPhone project. Remarkably quick, great way to get an idea in someone's hands, rather than writing up a dry, flat specification.
Basically, you create the screens in Powerpoint, export them to jpegs, upload them to Invision, and then just run through and add clickable areas. Great for simplifying content flows, and makes it very obvious when there's a gap in your information architecture.
Running up a 20 screen prototype took about 2 hours. I had it in the client's hands 3 hours later, and had sign off on the project in about 15 minutes.
