Some riders rig cords at their waist and down their pant legs that they can yank to release, if necessary. Some of them will niftily screw onto the ski pole-probes I just talked you out of. Folding models take up less space and prevent the teeth from chewing your spare sweater, but some of the hinges are obnoxious and tend to collapse while you're using the saw. Get one, or the pieces you feel you need, if it will remind you to pay attention to the snow and the weather. The idea is that if the recreationist gets buried, some part of the cord will probably remain on the surface.
Searchers can follow the directional arrows printed on the cord and locate the victim.
Avalanche cords tied to your skis are a great way to find them when they shoot off your feet on a powder day. The Black Diamond AvaLung is an interesting new product. It consists of a zippered mesh vest with handy pockets and a breathing tube attached to a snow filter on the side. The idea is that if you are caught and buried, the tube and one way valve allows you to vent your hot, CO2-rich breath out the back. This prevents CO2 narcosos and the icing up that ordinarily forms a fatal ice-mask that seals the porous snow, preventing you from breathing the supply of air that exists in even the densest snowpack .