EVE Online, from mission-running and ratting to trading and research. Some methods, like mission-running, are very active processes in which the amount of ISK made is directly proportional to the amount of time spent playing. Other processes, such as trading or moon-mining, are largely passive endeavours in which ISK is made even while the pilot is offline. One such source of passive income, which has been around since the tech 2 invention system came in, is datacore collection. Players with high enough standings and the right skills trained in the science field can sign up to do research with various R&D agents throughout EVE. The agents automatically give players research points every day for free, which can later be redeemed for datacores to be sold on the market.
Datacore collection itself is an intended game mechanic, and this system for supplying datacores doesn't look like it will be changing any time soon. The issue is that characters on expired accounts will still accrue research points every day. Using this so-called "ghost research" loophole, some players have been farming datacores with an unfair advantage over active pilots. Abusers typically set up accounts with three research characters each, then let those accounts expire. Several months later, each account will be re-activated to harvest the datacores. In a recent devblog, CCP Soundwave explained that this issue came from a list of important player-voted issues that was presented to CCP by the Council of Stellar Management. The unintended loophole will be closed in a hotfix in the near future.