Interesting ... something useful in a variety of ways - how often are we on the phone or on IM brainstorming with someone (or a group) and we simply want to share a screen to add richer context to the conversation or interact in real-time around whatever it is that we are talking about without experiencing the heaviness of a high-end web conferencing tool? I imagine that we would all like to have something quick and simple like this. Adding VoIP would be a natural extension ... the Tahiti site.
Microsoft today launched a free screen sharing software for Windows XP and Vista users. The software ("Tahiti") can also be used for providing remote tech support or co-authoring presentations and documents with far-away colleagues. [If you need a Tahiti invite, drop in a comment.]
The workflow is simple - download and install the Tahiti software (~2.5 MB), login with your Windows Live ID and you are ready to share your entire desktop, web browser or any program application with the world.
The desktop screen can be simultaneously shared with upto 15 people at a time and the person sharing can give control to anyone else who's also part of the screen sharing session. And each participant has a personalized mouse pointer to point out specific items or highlight an area of shared screen.