If you want a super easy way to do this, plug a camera into a computer and head over to
http://www.stickam.com. The site allows you to create a channel that broadcasts your video, and others can watch. You can set the room to private, so only users you allow in will be able to enter, and if they have cameras on their end, they can connect them, and you can have an interactive conference.
The picture quality isn't great, but it is a lower bandwidth solution.
Just a thought.