Amethyst (as a homage to Quartz from WoW) is a customizable CastBar replacement for WAR.

It comes with a configuration GUI that can be accessed with /amethyst or /amt

New in 1.4:
SharedAssets Implementation. You can now choose the texture of the cast bar.

New in 1.3:
AmethystEffects is a Plugin that displays the time left of your buffs and debuffs on your targets. You can configure it through the same GUI. If you don't want to use the functionality, you can disable the Plugin in the /addon-Menu.

Dependencies:
This Addon uses LibSlash for slash commands.

A note about the compensate latency option: WAR is quite laggy when it comes to spellcasting. Often a spell won't fire until half a second after the cast is done. Generally, the CastBar won't hide for that additional duration, yet you can move around, the cast will be displayed as aborted but still get fired. 'compansate latency' simply hides the cast bar when the spell is done on the server, so you know when you can move again (or whatever else). In very rare cases this can lead to problems with spell pushback, but shouldn't do so normally.