haha , if you are referring to the other thread, it's just a "Butter".
a butter is when you lean forwards or backwards on your skis, flexing them, and spinning on the snow at the same time. while you are spinning, the skis are only touching the ground in the direction you are leaning,... ie if you are leaning forward, the noses of your skis are on the ground, your skis are bent so your tails are off the ground. That's a "nose butter", and a "tail butter" is just the opposite.
this vid shows it pretty well:
after you put all that pressure on your skis, you can pop off the springloaded tips and tails, as TJ schiller so awesomly demonstrates: