Foursquare Tip: Unlock your (RED) badge today! Last Updated December 1, 2010 By Craig Smith Filed Under: Social Media Foursquare is honoring World Aids Day today by teaming up with the (RED) for a new badge. Be Part of the Newest Social Network That Everyone is Talking About!. Join Today. Including #turnRED in a checkin today will unlock the badge and help turn the world red with awareness! There are over 400 stat posts on DMR. Browse the full list here.