Here are my two examples of this glitch.
http://bgoatclan.com/forums/index.php?showtopic=763 That one is for "2 player only"
http://bgoatclan.com/forums/index.php?showtopic=760 That one he will not reveal the secret.
Me and my friend were bored and trying these ones, I showed him them and he went around doing them in 2 player. After we both went back to Career mode, he freaked and said YOU GOTTA SEE THIS. You can do the glitch from the first link in career mode. (May be old news) Its almost the second one except you dont get the points so easily.
1) Go to any Quaterpipe/Halfpipe, etc.
2) Ollie out of the QP/HP and hold down LB+RB+L1+R1
3) Still holding LB+L1+R1, keep on tapping RB.
4) You should be getting higher slowly.
5) Next, Hold down RB+L1+R1 and keep tapping LB, you will get even higher.
6) One you are high enough, keep on pressing LB+RB+L1+R1 simotanously (major sp)
7) You should get a pretty big combo easily.
8) If you go high enough the screen will turn black (just happened to me) and I got a 20x backflip and a 50,000 spin.