Some time ago the ATC2K action cam was launched. it can record 30 minutes of video on a flash card, intended to film action sports and waterproof up to 3 meters (I dove to 7 meters with it before I modded it..)
Generally it is a very nice cam, but for the extremely narrow angle of view. This is even worse under water. The manufacturer since created the ATC-3k and ATC-5k with a wider view. If you want a
new wide(r) angle cam, buy these. But if you still have an old ATC2K, this is for you.
Several action sports people have modded their atc2K to have a wide angle lens. These mods generally ruined the waterproofing and used large/expensive/professional wide angle lenses
This is my mod of the ATC2K, preserving the waterproofing of the cam, and keeping it small.
This was important for me as my hobby is building and driving R/C model submarines
(have a look at http://www.subcommittee.com
if you are curious). We strap the
cam on the back of a submarine.