Cornell University has paid for the web conferencing service, WebEx, which provides on-demand, real-time, collaborative web meetings and conferencing. As part of Cornell's campuswide license, faculty and staff can schedule meetings that anyone can participate or present in.
For more details, see: http://www.it.cornell.edu/services/webconferencing/
On that page:
Click "Set Up" button on left-hand side of page to start setting up WebEx on your computer:
Click "Meeting Manager button under "Set Up" to continue setting up WebEx on your computer:
Click "Set Up" button on right-hand side of page to finish setting up WebEx on your computer:
You can also click "verify your rich media players" button to verify that QuickTime and Real Player are properly set up for use in WebEx (note that the verify page will probably fail to verify the Windows Media Player, but Windows Media is used very rarely, if ever)