The drapey shirt thing that makes it look like she's wearing actual clothes as opposed to ~sexy armor~. They're mostly for guild members to display that they are in a certain guild, but some tabards can be earned from NPCs during quests and the like. Like this one!

I, too, love that the goggles have an armor rating. Sadly, I'm eventually going to have to swap them out for a helmet once my character starts being high level enough to wear one because both the goggles and the helmet would be equipped in the same slot. :( Now how will people know my character is an engineer?