Links:

Skype.com
Download Skype Windows Mac
Getting Started Info & Guides
Adding Contacts Guide
Setting up Video Guide

Skype is my top choice for videoconferencing. It works with both Windows and Mac and has the highest quality video. Skype is also easy to setup and use. Skype's main market is VOIP (Voice over IP) which allows you to use your computer to call regular telephone numbers. If your main goal for using Skype is for videoconferencing, then you can ignore all the phone information.

System requirements PC

• PC running Windows 2000, XP or Vista. (Windows 2000 users require DirectX 9.0 for video calls).
• Internet connection (broadband is best, GPRS is not supported for voice calls, and results may vary on a satellite connection).
• Speakers and microphone - built-in or separate.
• For voice and video calls we recommend a computer with at least a 1GHz processor, 256 MB RAM and of course a webcam.
• For High Quality Video calls you will need a high quality video webcam and software, a dual-core processor computer and a fast broadband connection (384 kbps).

System requirements Mac

• Mac computer with G4 800 Mhz processor or faster.
• Mac OS X v10.3.9 Panther or later.
• For higher-resolution video a faster processor (Core 2 Duo) and a broadband connection with at least 384kpbs upload speeds.
• 512 MB RAM.
• 40 MB free disk space on your hard drive.
• Microphone and speakers or headset.
• Download drivers for your webcam.
• Internet connection (broadband is best, GPRS is not supported for voice calls, and results may vary on a satellite connection).