Guild Wars 2

The description says, “Double-click to gain a buff that increases your chance to gain bonus experience from crafting by 50% for one hour.”

Is this bonus xp to the crafting skill you’re training, or your actual xp?

“The boost increases bonus crafting experience, but does not affect experience towards leveling. In other words, you use fewer materials in order to gain crafting ranks.”

http://wiki.guildwars2.com/wiki/Crafting_Booster