For some of us Steve Coogan's spoof film Cruise of the Gods, based on a nonexistent 1980s sci-fi series, The Children of Castor, was the first inkling that such things as fan cruises exist. In fact, they're big business.
As we speak a bunch of Trekkies is cruising down the Danube. Next year the same company, Cruise Trek (www.cruisetrek.com), will be boldly going to Bermuda.
At least Trekkies are legion. Who ever heard of Boopies? Yet Betty Boop fans are even now recovering from a five-day jaunt from San Diego to Mexico (www.bettyboop fancruise.com). Along the way they had a "once in a lifetime opportunity", as the tour organiser put it, to get their photograph taken with Betty and get her autograph. Boop, lest there be any confusion, is a cartoon character.
In January there's Cruise with the King, a tribute to Elvis Presley (www. mahwey.com). Guys, Elvis has left the boat.
Yet compared with some other themed cruises, fan cruises seem positively sane. Continuing Education dental cruises, for example, combine voyages around the Caribbean with seminar topics such as "infection control" and "meth mouth".
Sooner a dose of that than the even less interesting sounding Bingo Cruise, even if it does incorporate the World Bingo Championships.
The same company (www.specialeventcruises.com) hosts the annual Crossword University Cruise, next scheduled to set sail in January. First letter B, rhymes with snoring. Then again, whatever floats your boat.