I spotted this whilst browsing. In view of the well-travelled nature of some of the contributors to this group, I thought it worth posting.
You will now need Health Insurance if you are going to the Isle of Man. They are not in the EU, and there is now no reciprocal health agreement with the UK. This means if you are taken ill or have an accident whilst over there you will have to pay all cost which could involve having to pay for medical flight to Liverpool or elsewhere.
From 2014 you will need your passport to get onto the island anyway you travel.