Time for me to add another video. Now, this one I experienced first-hand, so it will come with a story.
This happened right after the release of Guild Wars 2 mmo. I believe, it happened during first week. There were traders in game that sold high-level weapons for karma - in-game currency. Those weapons cost many thousands of karma, but on one traider devs forgot to add those 3 zeroes. So, when someone found out that you can get dirt-cheap high-level weapons, the mind of the people was blown. And that was just part of it. Weapons were good, but you could buy like 100 of them easy and re-forge them in mystic forge to create even more powerful weapons of the highest grade and level. MMO players would know how awesome that is.
When rumor spread, every second person online went to do this. Literally thousands of people, all guided by the common thought - this is too wide-spread to ban for this, and this is a mistake on devs part, not ours. Right? Riiight. Next day all those thousands of people were banned. Forever, as it said at first. No guild, no server was left unharmed.
But still, it WAS too wide-spread, so developers of the game gave us this option - we could write them a ticket to support, stating what items we got and promising to get rid of them when we are unbanned. And that what we did. In the end, this whole thing cost me 3 days of ban, but it was fun enough experience. And one player, after all this, went and made this great song with some in-game footage:
(If you go to youtube link, there are lyrics there)