Check out Exchange 2007 for 5 days
Steve lead me to this following link on Brett's site. Basically it will allow you to trial Exchange 2007. You can create a temporary account to experience the features of Exchange Server 2007 which will stay active for 5 days. Your account will be pre-populated with sample messages, calendar appointments and contacts to help you have a rich experience. You will be able to send and receive mail, schedule meetings, and adjust your options.
Check it out here
