Clarizen project URL

If your needing to include the link in emails this is fairly easy;

using the 'share' option on the button ribbon just below the project name (in the project page) you can select 'link' which will provide you with the URL for the project.  Don't forget though that anyone trying to open the link will need to be an active user of your installation. 

If you need to use with exterior people, then I'd suggest using the widget (Same menu option) which will give you a link that provides a 'read only' version of the project.

Hope that helps!

I should have been more specific. I understand the share functionality but I'm really trying to create the URL from, for example, a system generated email.

This is where the gethyperlink() function comes in handy. You can use gethyperlink($Project) in your configurations, workflow rule, and email notifications to provide a clickable link to the project.