Having tried it and failed some time ago, when our local network was weirdly set up and our bandwidth limit lower, I hadn't bothered trying Skype again until just recently.
Skype is absolutely great. How else can you conference-call between Australia, England, and America, and just chat for four hours or more, without paying a thing? It's been of great encouragement to me to talk to Marah and Thierran, not to mention the fun of chatting about random bits and pieces!!
VOIP (you mean those planes that can take off like a helicopter? Oh! Voice over IP! IP? IP!) is the way to do things. You don't even need a crash-hot internet connection... although it does help. But get yourself a set of headphones, otherwise everything will feed back badly.