The Microsoft Product is called Skydrive. You can go to their site to learn more about it. It lets you share documents on Microsoft products. Not every one needs to have the product loaded on their machine. They have been testing it on the University of Washington campus this year with great success.

I looked at Slide Share. It looks pretty simple to use. You upload your powerpoints for others to use. I had difficulty getting to the google app this morning, so I didn't look at that one. I agree that Prezi looked cool, but looked time consuming to use. Microsoft also lets you share powerpoints through its office live. They also have one out called sky -------- (something) to share documents. It is suppose to be available this spring. I get the name for you later so you can look it up on their site.