Zenbe is more than email. It seamlessly integrates all of your online communication. You don't have to open one window for your mail, another for your calendar, one for your tasks, etc. Zenbe includes a calendar, daily agenda, address book, and task lists, all designed to work together.
Zenbe is extensible, allowing you to add modules from third parties. See what your Facebook friends are up to at a glance, chat with your Gtalk buddies, scan your favorite RSS feeds, all without leaving your email.