#Now you don't need a computer to be in a G+ Hangout

#18.

Yes this is cool. Now you can make call from inside a hangout. This means people no longer have to be by a computer, or even have a Google account to join a G+ video chat. You just call them up and their voice can be heard by anyone in the Hangout, and they can listen in on the session.

This new feature is initially available inside Hangouts with extras. 

This is how you do it:

1. Click Invite at the top of the hangouts with extras window
2. Click the Phone tab on the left of the window, and enter the phone number you wish to call.
3. Click Call now.

This was put up be Google employee Jarkko Oikarinen in his public post.

It seems it is currently free in US and Canada but lets hope there's more to come.