It comes as no surprise that a large number of Americans fantasize about being rich. According to a 2008 report by the Pew Research Center, more than 55% of Americans rank becoming wealthy as "important" (43%) or "very important" (13%).

Who wouldn't want to be rich?

The answer is more complicated than you might think. Here we look at millionaires who, rather than living rich, decided to give it all away.

The $7 Million Secret
Grace Groner, a "friendly" and "unassuming" woman from Lake Forest, Illinois, made prime-time news last week when she passed away at the age of 100. The publicity shone a light as much on her modest life as what she left behind - $7 million dollars, which she donated to her alma mater, Lake Forest College. Although Groner was single and could have lived the high life, she preferred her tiny one-bedroom house and frugal lifestyle.

Her fortune came from shares of stock in Abbott Laboratories (NYSE:ABT), where she worked as a secretary for 43 years. Groner bought the shares 1935 for $60 apiece. By the time Groner passed away, these three shares, along with reinvested dividends, were worth $7 million. She donated every cent to Lake Forest College to be used for scholarships. (For more insight into how Groner grew such a large fortune, see Steady Growth Stocks Win The Race.)

From Alpine Villa to Mountain Hut
Austrian businessman Karl Rabeder has all the trappings of wealth: luxury cars, beautiful homes and a lavish lifestyle furnished by his nearly $4.7 million net worth, but he doesn't care for any of it.

The 47-year-old Rabeder made his fortune by selling interior furnishings and accessories, but told U.K. the The Daily Telegraph in February that his five-star lifestyle was "soulless," and he felt that he was a "a slave for things [he] did not wish or need."

So Rabeder is packing his bags and moving from his 3,500 square foot villa in the Alps and moving to a wooden hut in the Austrian mountains. His money will go to charities he set up in Central and South America. (A smaller home can really cut your cost of living. See Downsize Your Home To Downsize Expenses to learn more.)

An Entrepreneur's Grass-Roots Movement
Millard Fuller became a millionaire before he was 30 years old by forming the direct marketing company Morris Dees, which sold cookbooks and candy to high school chapters of the Future Homemakers of America. But rather than kick back and enjoy the fruits of his labor, he gave it all away, sold nearly everything he had and set out to find a mission.

It was in Americus, Georgia, that Fuller and his wife found what they were looking for: inspiration. It was there that the Fullers came up with the idea of building no-interest housing for the poor, an idea that eventually lead to the creation of Habitat for Humanity, which has since become an international organization that has built more than 300,000 homes in 93 countries. Fuller died in February 2009 at the age of 74.

A $15 Wristwatch, a $1.6 Billion Donation
New-Jersey born Charles "Chuck" F. Feeney made much of his fortune through his Duty Free Shoppers airport gift shop - but you'd never have known it, and he wasn't about to tell. In fact, Feeney is famously frugal, and went to great lengths to conceal his wealth - and enormous philanthropic donations - from the public.

When he sold Duty Free Shoppers in 1997, the shares he had transferred to his charitable foundation Atlantic Philanthropies 20 years earlier were worth $1.6 billion - all this from a man who doesn't own a home or a car and according to a 2008 piece in U.K. financial publisher Citywire, he appears to be "anything but the image of a wealthy businessman."

Atlantic Philanthropies' endowment is around $4 billion, and Feeney wants to see it empty its coffers by 2016; this means spending $400 million on charitable causes each year. (Want to live thrifty without having to look cheap? Read Save Without Sacrifice for tips.)

A Modest $100 Million Magnate
Have you ever heard of Priscilla Bullitt Collins? In not, you probably never will. The Seattle philanthropist passed away in June of 2003 at the age of 82 after having given away more than $100 million to causes that support the environment, education and the arts, but on one condition: that not one iota of this largess bear her name - ever.

Collins came to her fortune through the sale of King Broadcasting, which her mother, Dorothy Bullitt, founded. According to the New York Times, a Seattle newspaper once said she "looked like a cashier at a church bake sale".

She lived in a one-bedroom apartment and drove a beat-up yellow Datsun, but despite her frugal ways, she didn't have any trouble parting with her fortune and championing charitable causes, including the construction of a housing project for the working poor in a prime area of Seattle.

Omaha's Altruistic Oracle
What list of frugal philanthropists would be complete without Warren Buffett? The renowned investor and chairman of Berkshire Hathaway was ranked as the richest person in the world by Forbes in 2008 with a net worth of $62 billion. He dropped to second-richest in 2009 after he began moving funds to charity.

Famously, Buffett doesn't believe in "dynastic wealth" or five-star living, and in 2006 he announced that he would give his fortune to charity, mostly to the Bill & Melinda Gates Foundation. His pledge hardly represents his entire fortune, some of which he plans to leave to his heirs (in modest amounts), but don't assume Buffett's living the high life. The famously frugal investor still lives in the same Omaha house he bought in 1958, indulges in simple pleasures such as junk food and watching sports on TV. (To learn more, read Warren Buffett's Frugal, So Why Aren't You?)

The Bottom Line

These modest millionaires (and billionaires) defy our expectations of the super wealthy, and even of human nature. As it turns out, not everyone wants to be rich, and even those who think they do find that there are richer experiences than the luxuries their wealth affords.

Get on top of this week's most important financial news in minutes with Water Cooler Finance.