I was looking around on the internet the other day and came across this. Apparently, Britain had a plan to build ice ships for use in the atlantic. They would've been made out of ice mixed with wood pulp. I thought it was the most ridiculous idea that ive ever heard.
If you type in the name "habakkuk" in our search function, you will find a number of threads on the topic, dating from about six years ago I think. Still, and interesting topic. The ice wood pulp mix was called Pykrete (I think) and was very resilient to both impact and melting compared to "normal" ice.
The reason the project ended was the fact that it required the build-up of all-new infrastructure. Ships would have to be built up near the Arctic, where there aren't a lot of factories. Or people. or anything.
Actually, the infrastructure was largely put into place for building the ship. What ended the project was simply the realization that by late 1943 as construction got underway that it was no longer needed and by the time it was built the war likely would be over. I know in an earlier thread I posted up the location and details of the plant that was built. It included a wood pulping mill, several saw mills, and several refrigeration plants to make the blocks of pyecrete.
A quick forum search turned up several threads. Texson66 included this link. Habbakuk: The Iceberg Aircraft Carrier | Online Information Bank | Research Collections | Royal Naval Museum at Portsmouth Historic Dockyard. It probably contains whatever information you would want. Here is also a link to information from Mythbusters, which did a show on pycrete. MythBusters: HSW Explainer : Discovery Channel. Finally, here is the thread which contains one of the forum discussions. http://www.ww2f.com/wwii-today/31078-pykrete-mythbusters.html
This site has some interesting info on Project Habbakuk Project Habbakuk | Strange Weapon of the Week