Radvision demos integration with Windows RTC Server and Messenger

I've written a lot recently about Radvision and its slew of announcements. At the show this week, I got to see some of the stuff I've been writing about in action, specifically the company's new integration with Microsoft's Real-Time Communications (RTC) Server (formerly Greenwich) and Windows Messenger. Basically, Radvision is using Windows Messenger as the launching point into a multipoint call. FVC is also doing this with it's new Click to Meet Express 2.0 product. Because Windows Messenger uses SIP, one could just use a PC connected to broadband to make calls into the Radvision ViaIP 400 server and connect into a regular conference call. This functionality could be cool for a remote user like myself on the road with access to a robust network that needs to call into the office for a meeting or to check voicemail. Rather than using my cellphone minutes or an 800 number to call in, I could take advantage of the free Internet connection and place a free call. Maybe it is just a dream?