I figured I would create a thread here for Global Ignore List, should anyone want to discuss the add-on.
GIL is an addon that provides a greatly enhanced ignore system which works across all characters, servers, factions and even regions (for those PTR players). It allows for thousands of ignores, synchronizes the list across characters, provides the ability to ignore players, NPCs, and entire servers, as well as enhances the Blizzard UI with various ignore related things (such as ignoring by right click target portraits). It also has its own UI for managing the global list which allows for sorting and pruning.
The latest versions are always here and on Curse. See the link below for screenshots and more information: