[edit 2010-05-10] I posted this on my facebook account and received a well-deserved lambasting for up-voting the article.  I hadn’t thought hard enough on the problem of domain trusting with such a distributed, flexible, and multi-point service such as email.  Mat Whitney gave me a lesson on the difficulties of domain reputations when the domain [...]

We use Outlook 2007 at work to manage all our emails, calendars, and contacts.