But as Martin Hesp notes, even on a "calm" day you're in for serious chop.

Boreray 60 miles off mainland Scotland

Love the Scottish islands, but want something with a little more bite? Head west of the Outer Hebrides, and you'll find the archipelago of St. Kilda, 40 miles into the Atlantic.

It's one of Scotland's five World Heritage sites, with a main island that was abandoned in the 1930s when crops failed. Imagine the surprise of archaeologists when they found that one of the least hospitable islands, Boreray, was occupied in prehistoric times.

Reaching Boreray: Since Boreray comes under the protection of the National Trust for Scotland, you need its permission to visit.

Then? Lots of time and lots of luck -- with a rugged shoreline and savage sea swell, this isn't an island built for landings.

According to one guide, more people have reached the summit of Everest than have landed at Boreray since the National Trust took ownership in 1957.

North Sentinel Island 400 miles from Myanmar

North Sentinel is one of the 572 islands making up the Andaman chain in the Indian Ocean's Bay of Bengal.

It's surrounded by dangerous reefs, but North Sentinel is intimidating because of its inhabitants. The Sentinelese want nothing to do with the modern world and have repeatedly rebuffed attempts to make peaceful contact.

Reaching North Sentinel Island: You're kidding, right? If the above description didn't put you off, this article about a pair of fishermen who strayed onto the island certainly should.

Rockall 270 miles from Ireland

If you think Boreray sounds forbidding, try sailing 187 miles west of it. Rockall is the tip of an extinct volcano reaching 20 meters (about 65 feet) above sea level, in seas with waves recorded as high as 29 meters (95 feet).

In 1955, the British Empire, in its final territorial acquisition, seized Rockall -- allegedly due to fears the Soviets would build a missile battery on it.

Reaching Rockall: In the words of the recently minted Rockall Club, "visiting Rockall is difficult, completely weather dependent and not cheap."

Your best bet is contacting Kilda Cruises and arranging a tailor-made excursion. Or you could sail there, lash yourself to the rock and claim it as your very own micronation -- but you wouldn't be the first.