Instantly swap your main class and secondary class when using the Housekeeper or Class Master NPC. This reduces class changing from 8 clicks to only 2 clicks! You might even consider it 1 click if you don't count clicking the NPC ;)
Now only two clicks (click npc, click "change class"). Thanks to Alleris... *wink*. As a result, the Swap button was removed. Use version 0.3 if you don't like it.