Consolation bags (popularly called "failbags") are awarded as consolation prizes to players who defeat a boss encounter in a Raid Finder mode of a raid instance, or any of the Pandaria world bosses, but are not awarded loot.
They generally contain roughly 28
50
(for Mists of Pandaria-level bags), and (as of Patch 5.2) have a slim chance of containing useful items like 
[Mote of Harmony], 
[Spirit of Harmony], elixirs/potions/flasks, and uncut gems. Additionally, bags rarely may contain companions and raid-finder level trash drops that were not otherwise obtainable.
Pages in category "Consolation bags"
The following 12 pages are in this category, out of 12 total.