One very quick technique is the stomper belay, also known as the carabiner/ice-axe belay. This technique takes mere moments to employ and is very effective in places where it is easy and safe to stand.
To set-up this belay, stomp your ice axe into the snow. Clip a carabiner to the head of the axe and then clip the rope to the carabiner. Step on top of the axe to hold it in and then belay off your body using a hip belay, a shoulder belay or a device off your harness.
In this second photo, Mike demonstrates a stomper belay with a shoulder belay. Shoulder belays are almost never as effective as hip belays and indeed, it is a bit painful to hold a fall on a shoulder belay with a stomper belay, whereas one barely feels it when set-up on a hip belay.
One note of caution, the rope should always be clipped cleanly through a carabiner on the head of the axe. The rope should NEVER be set-up on the carabiner as a munter-hitch. There was a major accident in Canada when this was done inappropriately, and the rope ran from the climber to a munter-hitch on the head of the axe and then up to the hip-belay. And unfortunately, there were fatalities as a result of this mistake.
As with any new technique, it's good to practice in terrain where there are no consequences. Try the stomper belay with a partner on low angle terrain. Have your partner take mock falls and see how it feels. Try each of the different belay styles, off the hip, off the shoulder and off the harness and see what works best for you.
The stomper belay is a very nice little technique to have in your toolbox. When used correctly it is fast, efficient and very effective...
--Jason D. Martin