1 - Does not require the base game to add to your account. 2 - Requires you to install/add the free base game to your account first.
Feel free to add your own links if I've missed anything.
Updates 22 October 2014 - Lots of new content added. 6 January 2015 - Added DLC for Aura Kingdom, Depth, Dreaming Sarah, Enforce, Facerig, Out of the Park Baseball 15, PAYDAY 2 19 March 2015 - Added many suggestions by Kyzent