A Few Tricks

Flipping in the air 4 times without jumping off a cliff:
1. Press space to jump
2. As soon as you do that, press x to flip
3. When the first flip is finished, press x again. Or, you could have just held down x.
4. As soon as the second flip is finished, press space again to jump in the air.
5. Repeat 2 and 3.
6. Land and wait for the applause.

Leaning forwards while standing:
1. Press W and then space as fast as possible
2. You will lean forward and then stand back up

Sky Diving
1. Fly up to an altitude of 79 (the max)
2. Turn off flight
3. Geronimooooooooooooo!

Get stuck in the air while attacking or doing a skill
1. Get within range of the enemy to do your attack/skill
2. Hit the attack/skill hotkey
3. As soon as you do that, hold down space to jump
4. You'll be in the air, doing your attack/skill
Note: This might not work if you're not laggy enough.