Well, a new one coming out is called Google Wave, and this particular product has me very excited!
What has me jumping up and down in anticipation?
Well, beyond the obvious cool reasons of spending vast amounts of my personal time collaborating (and arguing) with people on the best Bulgogi recipe (and my research in physics and other topics), with respect to teaching critical thinking skills I can see the promise of Google Wave.
For instance, I could use GW to form a collaborative exploration of a topic found on the web, such as a CNN article mistating or sensationalizing opinion as fact. The users could start researching the claims made in the article, and using a group white board with a Google Voice conference call work on determining the real meaning of the data used in the article, and what impact there is on their personal life.
Of course, I can see a lot of arguing over opinions, and ideals etc... but what is new there... at least with GW you can have the ability to see the angry or smiling faces of the collaborators rather than relying on emoticons to convey a j/k. ;)