Do the quest on ultimate, after defeating dragon go back to Forest 2, press the switch in first room to elevate a bridge, a computer will allow you to warp in Spaceship.
If you die it's over, if you survive another computer will either give you a reward or make you crash (if not P1 I believe).
About the TP, I think this is priceless.
As Midori stated, it's pretty much useless but nobody farm for this.
(250 PD for 250 extra TP while Trifluids are free ... what a waste)
I wonder how much would have Monogrinders gone for if it happened to have a 1/100'000 drop rate.