Global Calendar

I am looking for a global Web Calendar that I can put on my intranet. I have Exchange 5.5. I want 10 Top Level People to share this calendar. What I want is that if 1 user creates an entry in this calendar on my intranet, it should send an e-mail with an attachement to the rest of the 9 people and then that entry gets updated on their individual calendars on their outlook. Has anyone used any products that can do this? I have looked around at Slipstick but not getting anywhere.