With the new possibility to change servers on-the-fly, you might wonder if you're back on your home server, or somewhere else. WhereAmI remedies this by showing the current server name next to the scene name on the minimap.
Use /wai left or /wai right to move the server name to the left/right of the scene name. Default is left, since there's often not enough space on the right. This setting is saved when logging out/in, and the same for all your characters.
Use /wai hide to hide the server name, or /wai show to show it again. This setting is not saved to prevent people from wondering where the server name went.