... Bouncing on the front wheel
OK, that one is not really a trialsy move, though on some occasions, you may have to bounce your front wheel away from a cup or stuck position, if you are rolling down some very steep terrain. But it is a nice and easy trick to please a crowd at a demo.

Assuming you master the endo, just pull the smoothest one you can.
1° Reach balance on top of the front wheel, keep your arms straight, and flex your knees to lower your body on the bike. 2° Arms stretched, give a very brief impulsion with your legs (extending again from the folded knees position). This compresses the tyre. 3° Exploit the bouncing effect from the compressed tyre by folding your knees back again, and let the whole bike bounce.
See the move in a video

video
Bouncing back, up a wet slope
How to do it?
To maintain your balance on the front wheel, you really need to keep your whole body above the front hub. Don't try to pull the bike up with your arms, but instead, rely on your legs and body weight to do the work. The whole trick consists in compressing the front tyre (low pressure helps) so that it bounces back (at that time you just fold the knees back). The arms should really be locked in a stretched position, and the feet can actually pull the bike backwards by gripping vertically on the pedals. To turn around while bouncing, slightly twist the bars on every bounce.
video
Bouncing 360°

video
Bouncing the front wheel
away from a pot hole.
What is it good for?
Rolling down some steep terrains, or in rocky zones, the front wheel can get stuck in a pot hole, with all your weight on the front wheel. The only way out (apart from a crash over the bars) is to bounce the front wheel off the pot hole. You'll have much more power and bouncing effect using an impulsion with your legs than pumping with your arms, so don't waste your energy. When you are confident on the front wheel, you can try out some nose wheelings (rolling down any odd slope by release the brakes progressively and maintaining your center of gravity well above the hub). A little bit trickier, you can roll backwards down a slope (if you don't care too much about face plants). just fo
video
Nose wheeling down a slope