What is your favorite Clarizen feature?

I think it would be fun to hear everyone's favorite Clarizen feature. Is it the Roadmap? Multi-Gantt? Reporting Progress over Email? What's your favorite?

the collaberation is great!
the concept allowing the management of resource load is also important
the ability to develope reports independantly is a wow!
the resource management perception embedded in the system - with the planned developement can be a dream come true

Waiting for v4.0 and expecting it to be the ability to use GROUPS!

My favorite feature is having the ability to mark each milestone/sub-milestone with a percent completed. This feature helps put my mind at ease because I can see where the progress on that particular job is at. In addition to the percentage complete option I love the alerts on the home page, this allows me to immediately view what projects need updates or re-reviewed for the sake of keeping the project on time and within budget.

Thanks for all of the posts so far!