Another reason to join Google +, if you haven’t already, is the new remote desktop feature available in Google Hangouts. This gives you the ability to work on someone else’s desktop to demonstrate or troubleshoot while you are chatting in a hangout.
The feature is listed under the Hangout Apps menu.
If you are teaching online classes using software that does not allow for remote desktop work, adding Google Hangouts to your repertoire of tools might be a good idea. There is existing software that gives you remote desktop access, of course. LogMeIn and GoToMyPC probably are the best known. Will Google + overwhelm them?