Here's a rumor about Half-Life 3, via a game listing for this week's Gamescom show. Here's good reason to be skeptical.

DISCUSSION

Apparently it was a mistake: eurogamer.net

Fine don't link, edit: http://www.eurogamer.net/articles/2012-08-14-gamescom-claims-half-life-3-and-dragon-age-3-will-be-at-show