Today a client of mine, Mint, announced their application at Techcrunch 40. It's a finance tool that lets people track and monitor their accounts without routine effort. Which people? It turns out that the folks at Mint have studied their audiences carefully and selected the group of people for whom applications like Quicken are too demanding. I sat down with Mint's CEO and head of UX design and sketched out their understanding of this audience's mental model on the whiteboard, and within a few hours we shifted the navigation for the application into a representation of how these users approach their money. The most interesting mental space to me is "Spending Trends." Go make yourself a login and take a look at how much you spend at your favorite chocolate-maker each week.