Free Anytime Online Collaboration

I recently ran into a site called Vyew.com which specializes in live web conferencing. Vyew can be used for real-time online collaboration, you can use all types of content (ie. PowerPoint, Excel, Word, Images, PDF, RTF, etc.). Vyew uses VoIP (Voice Over IP) which allows users to simply use a PC mic to communicate with each other, no need to use a phone to interact. I love the simplicity of this tool, it's about as easy as working with PowerPoint. Another great feature from Vyew is "desktop sharing" which allows the presenter to share their desktop with other users. Of course the best part about Vyew is that it's FREE!