The GBase is a directory of gamification software providers run by the guys behind the GSummit conference and GsummitX meetups.
http://www.gamification.co/gbase/main/categories/design/leaderboarded/
Interestingly, we have been put in the ‘Design’ category – perhaps that’s because Leaderboarded allows 100% creative control of your Leaderboards and a personalized experience for players – all using our simple template system.