VoIP for the OpenSource Community

We are setting up a modest sized VoIP server for use within CentOS. Something that we can connect to for meetings, chats etc. And I was thinking, how cool would it be if there was such a thing - for any open source project to use. Most stable projects tend to be more than 1 person these days, and most of them tend to be spread over a wide enough area that conventional pots based conf calls are both expensive and hard to get going ( not everyone has a phone service capable of running a conf call, for example ). Since a voip client is included in pretty much every linux distro these days ( or heck, any OS released in the last few years has multiple options on free / cheap voip clients ) being able to get onto a conf call with other project members for regular sync up's would be great.

We have started doing this within CentOS for some new projects and infrastructure work, and its fantastic. You save so much time when using voice, rather than IRC and it also allows you to do stuff like talk through a shared screen session or a shared VNC session to do real work in sync.

Something like voip.osuosl.org for example would be nice. My guess is that the biggest app for this would be the conf call facilities, and perhaps a few static extensions per project. I wonder what would be involved in setting this up. Bandwidth is hardly an issue these days. CPU and Drive performance isnt much of a consideration either. So whats the blocker ? is it that no one has thought of this before ? or is it that there might be too many hours required on the admin side of things to keep tabs on stuff ?

Btw, I did pass this idea past Jeff Sheltren ( http://sheltren.com/ ) who seemed quite keen and which is why my example has osuosl.org url in there.

- KB