[35] Open DontStayIn Clubbing (primarily UK)   Open Draugiem.lv General (primarily LV, LT, HU) 2,400,000 Invitation only Haut de page Elftown Community and wiki around Fantasy and sci-fi . 185,000 [36] Open, approval needed Epernicus For research scientists   Open Eons.com For baby boomers   Open to people 13 and older