Gaia Hangouts existed for a short time in 2005 (Tue Feb 15, 2005). When visiting someones profile, you had the choice of choosing to hang out with the person. If he/she accepted, their avatar would appear on the left side of your screen and yours on theirs. You would also be able to send them hugs, kisses, and messages.
The Gaia Hangouts system was disabled after a short time being in existence. The reason's for it's removal could have been anything from the constant glitches making it shut down for maintenance commonly, or it's potential for cybering in ways the moderators could not control.