Hi all,
Chris you beat me to it.
My friends and I use Sailboard Masts almost exclusivly in both Carbon and Alloy, they have proven to be more than up to the job for booms and poles. The tapers allow you to reduce weight and windage at the outer ends where the stiffness is not needed.
Second hand one piece Sailboard Masts are very cheap in OZ, of course you have to look closely at what you are buying but misuse is generaly easy to see. The Alloy masts are getting harder to find, but if you can find Serfiac a european brand which I believe where very popular in UK as well as OZ they are excellent, anodised models are very resistant to corosion. The carbon mast vary alot in stiffness and strength racing mast are stiffer, wave masts are stronger.
Regards Gary.