Huddle allows you to push your tasks into a calendar application such as Outlook. The iCal button is located on the workspace overview above the right hand side of the calendar:
Clicking this will result in a popup that looks similar to this:
This popup will change depending on what internet browser you are using. The picture above is what you would see if you were using Mozilla Firefox and trying to bring the calendar into Outlook.
From this point, follow the instructions to import your Huddle calendar into your calendar application.