To do the Rolling Body(glitch not hint), hit Jump, Grab, Jump(X, O, X). Very interesting glitch.
NOTE: This works better when you have the SLOW MOTION JUMP Thievius Raccoonus page.
NOTE2: This may not work for official version.
The Froggy Airhop is something I found out using the Rolling Body. If you hit Jump, Grab, Jump, Grab (X, O, X, O) you will jump, make a brief grabbing motion, push your feet out like a frog, and do another grabbing motion. This goes higher than the Double Jump.
NOTE: This may not work in official version.