You have reached Peak 20. You have maxed out all your skills. You keep running instances and farming gear. Your TP keeps piling up, sitting uselessly on your primary class.
It would be nice to have a way to do something with it. I suggest a Skill Transfer Stone. two would be even nicer- a less expensive "bound" stone that lets you move some of your TP to other classes on the same character and a more expensive "unbound" stone that you can send to other characters or even put in the Auction House. Diamonds spent on these stones by players would benefit Gameforge's bottom line and the stones themselves would help players.