Hoi,
Sorry to bother you with this; many wikimedians use skype for Voice over IP (internet telephony) it is great software. It is really cool to be able to speak to someone in Australia and it costing nothing. Anyway, there is a new version for both the Macintosh and the Windows platform. The quality of service has improved.
If you already use skype, look under help and check if there is a newer version.
If you do not have skype, give it a spin. It is cool.
Thanks, GerardM skype: gerardmeijssen