The Cliffs of Moher are world famous and attract about one million visitors a year but only a hand full of people get the opportunity to kayak under these 700ft  goliaths.  This is a trip that ranks high on most sea kayaker's to do list and its one I was fortunate enough to bag on a spectacular Monday afternoon in June.

Above are some pictures of the Gopro mount I bought a few weeks ago.  It is very simple mount and doesn't take up much room on the deck or effect the stability of the kayak to much.   The mount is available on Ebay and other sites like Deal Extreme for about $20 - search "Gopro extension".  The suction mount comes separate.
 I have only used it on sea kayaks (plastic) and it has worked really well.  You do have to find a smooth surface for the suction cup to stick but this isn't and issue on composite kayaks.  I don't think that it will be ridged enough for white water as the impacts are very hard compared to sea kayaking.  Make sure to tether the camera to the deck lines just in case it comes off!

Here is the mount in action. Enjoy