For those seniors among us who are thinking of moving into an assisted living or retirement community, here's another alternative: Take a cruise. A long one. A really, really long one.

Permit me to back up a bit and explain. According to a recent AP story, two doctors at Northwestern University, Drs. Lee A. Lindquist and Robert M. Golub, have suggested that since the cost of a year in an assisted-living facility isn't markedly different from a year on a cruise ship, opting to cruise can make more sense. Cruises offer medical professionals on call, include meals, and feature plenty of recreation, such as movies, shows, libraries, and exercise. Plus, there's the extra perk of landing in new locales regularly. Travel can keep people more interested and involved with the world around them and gives them something to look forward to.

Estimated costs for a year in a double cabin on cruise lines such as Carnival (NYSE:CCL), Carnival PLC (NYSE:CUK), and Royal Caribbean (NYSE:RCL) are around $25,000 to $35,000, while assisted living facilities can cost between about $20,000 and $50,000 per year, depending on location and other factors.

It's true that most cruise lines may not be equipped to handle lots of long-term elderly passengers. But getting themselves up to speed might be worth it; there are tens of millions of Americans aged 65 and up and some 800,000 in assisted living facilities. Meanwhile, cruise industry stats reveal nearly 10 million taking cruises last year, more than 25% being 60 years old or older.

According to the story, the cruise industry isn't exhibiting much enthusiasm over the idea. Carnival and Royal Caribbean refused to comment on it. ".the International Council of Cruise Lines, a trade group that represents the major companies, doesn't think the industry is prepared to handle a large number of permanent residents with special medical needs. 'Cruises are intended to be a vacation. They're not intended to be a long-term assisted-living facility,' said council president Michael Crye. Cruise lines have also been marketing themselves to a more active crowd over the past two decades, getting away from an old saying that the typical passenger was 'newlywed, overfed or nearly dead.'"

So stay tuned for further developments, Fools. As baby boomers age, there may be increased interest in this idea, and it may change the business prospects of cruise companies. In the meantime, how prepared are you for your own retirement? If you want to be able to afford year-round cruising, you'll need to get your finances in order. Let us help you -- grab a free sample of our Rule Your Retirement newsletter, which can help you save big bucks for tomorrow. And discuss the topic on our Retirement Investing discussion board.

Oh, and if you'd rather invest in cruise companies than patronize them, check out these articles:

Longtime Fool contributor Selena Maranjian does not own shares of any companies mentioned in this article.