Some tricks in some order of difficulty:
- Hopping - Standing on the pedals, bouncing as if the unicycle were a pogo stick.
- One foot riding - One foot on a pedal, the other foot rests on the frame.
- Seat in front - Instead of sitting on the seat, it is held out in front with the hands.
- Wheel walking - Sitting on the seat, you walk backwards on the top of the wheel, propelling the unicycle forwards.
- One-footed wheel walking - As wheel walking, but you push the wheel with one foot, sliding it backwards to push again.
- Gliding - Sitting on the seat, one foot rests on the frame, the other touches the wheel as a brake. The amount of pressure adjusts the amount of breaking. This is started from speed, or can be performed downhill where a constant speed can be maintained.
- Coasting - Both feet resting on the frame. The arms are extended forwards and upwards, then waved to keep balance. This has to be started from speed, and downhill is not recommended. The world record (1998) stands at 144m.
Many of these tricks have variations and combinations. For instance, some of the better riders in the world will happily perform wheel-walking while standing on the frame. The greatest exponents will even coast standing up.
Basically, if you think a trick is physically possible (or even sometimes if you don't), then someone has probably tried it, and can either do it, or is working on it!