I've been asked quite a few times here recently along the lines of, "I want to play with MOSS to see what it's like - how can I?".
Microsoft provides a virtual hard drive that has a 30 day license of MOSS on it. You can download it here: http://www.microsoft.com/downloads/details.aspx?familyid=67f93dcb-ada8-4db5-a47b-df17e14b2c74&displaylang=en&tm.
To use it, you'll need Virtual Server: http://www.microsoft.com/windowsserversystem/virtualserver/
This download enables you evaluate Microsoft Office SharePoint Server 2007. Microsoft Office SharePoint Server 2007 is an integrated suite of server capabilities that can help improve organizational effectiveness by providing comprehensive content management and enterprise search, accelerating shared business processes, and facilitating information-sharing across boundaries for better business insight........
This fully functional pre-configured VHD provides you a trial software will automatically expire after 30 days.
This is a preconfigured virtual machine contained within the Virtual Hard Disk (VHD) format.......