SharedView lets you connect, share, review, and update documents with up to 15 people in a session in real time. Anyone can share, and the person sharing can give control to anyone else as long as they have downloaded the current release of this program.
Audio support is not currently available, so a telelphone call or an instant messaging program that supports Voice over IP (VoIP) can be used.
Microsoft SharedView & Dimdim are yet to be listed on Wikipedia's article on comparison of remote desktop software.