EPGP is a relational reward system for World of Warcraft. It is an alternative DKP system in which your loot buying power is defined by the ratio of your effort and rewards points instead of their difference. In plain English, in a traditional DKP system you receive effort points that increase your DKP pool and spend them to receive loot which decreases your DKP pool. The person with the largest DKP pool has the most buying power. In EPGP, you receive effort points but you also receive loot points. These are separate from each other and your buying power is defined by your effort points divided by your loot/gear points.
EPGP is implemented as an addon which you can download from the project's website or curse.com. The addon can work completely in game, using your guild's officer notes to store its data. As of Apr 2008, this website was launched, complementing the addon to provide a convenient way to access your EPGP data out of the game and at the same time protect it against accidental loss.
You can find more information about the EPGP system and addon in our Help section.