Teleconference between three or more people on Skype
Solution 1:
We've used WebEx at work with good results in the past. Supports both video conferencing as well as desktop sharing between clients. People can even dial in to a conference over the phone if they don't have a microphone.
Since you've said this is work-related, the cost at $49/month may not be too bad.
Solution 2:
Actually Skype themselves have now come up with a multi-user (up to 9) video conf. Tested it last week and it looks fine. At this writing it's in Beta, with a "free trial", though I can't see how they can charge for it while it's still in Beta...
Solution 3:
http://tinychat.com/
It's a web app so no software to install. It includes a chatroom feature and offers you option to record the conference. I find it pretty cool.
Solution 4:
Where this is an older question... newer advancements have been made in this arena. Google Plus now offers "Hangouts" where you can invite a group of people to a video-conference enabled chat session and interact freely over the web. It's free... and it works quite well.