VoIP in libraries

Using VoIP (Internet telephony) in an academic library setting makes a lot of sense. This is especially the case if you are offering distance education library services. Sherri Vokey of the University of Winnipeg is considering doing just that. I hope she'll post more about this. Most libraries now have access to the Internet but not all are able to afford a toll free line to help patrons living outside their area code. The free or low fee long distance services could be a pretty attractive option for libraries looking to provide this type of service or to expand existing services. I suspect that a large portion of distance learners are now doing their learning via computer and the Internet. While high speed connectivity is not ubiquitous in remote areas, my understanding of the technology is that it will function adequately with a dialup connection. If the patron is on the Internet anyway it seems a natural fit to have a librarian available to them via Internet telephony. Are there any libraries out there providing services this way? What has your experience been like?