This is a cute interaction for the input focus and data validation on Basecamp's registration form. The smiling character illustration on the left points out which steps are in focus. When an invalid value is entered, the character makes a concerned face and the pointing hand stays fixed on the highlighted input.
The illustrations on the site do a great job of making you feel like this isn't "business as usual," which is the reason for switching to Basecamp. Simple things that make the customer smile probably go a long way in this case.