I like Zoom (<a href="http:&#x2F;&#x2F;zoom.us&#x2F;" rel="nofollow">http:&#x2F;&#x2F;zoom.us&#x2F;</a>). I used to use Hangouts, but it consumed a lot of CPU. The free Zoom account allows you to have up to fifty people in a room for forty minutes, or an unlimited length call with just two participants.