What's a synchrotron?

Something that uses magnets, don't ask for anything else from the NZ Herald.
This gem:

A synchrotron is a machine about the size of a football field that accelerates electrons to almost the speed of light and is used for research in fields ranging from cancer radiation to engineering.

should be taken out and shot. Let's do a Feynman word switch and see if the sentence still makes sense...

A wobbldegokken is a machine about the size of a football field that accelerates electrons to almost the speed of light and is used for research in fields ranging from cancer radiation to engineering.

Hmmm, sounds suspiciously like this paragraph is the journalism equivalent of 'use this word in a sentence'. If i had to choose between the two, i'd choose the wobbldegokken, purely cause it sounds cool as it rolls of your tongue. In fact, you could replace the word synchrotron with pencil (and football field with... pen, and 'records thoughts') and the sentence would still be coherant adn true, if not just as equally vacuous.
Does it tell us anything about how these really fast electrons contribute to engineering and cancer radiation (not even sure about cancer radiation, i think they've screwed up there)? Why do we need a $200 million dollar piece of kit? What science is NZ going to do on it? What's the payoff (for those who demand instant gratification)?
If you want to learn anything more than how to spell synchrotron, as always, wiki has a good albeit brief entry here and here. Be careful, synchrotrons are the chemist/physicist's toy of choice so you are likely to find heavily technical stuff if you're not careful.