Each of these men is worth a fortune, though you might not know it by looking at them. Frugal, no-frills approaches have paid off in their businesses and their livesAt least once in your life -- maybe even once a week or once a day, for that matter -- you have fantasised about coming into a lot of money. What would you do if you were worth millions or even billions?Some of you may do nothing at all. Believe it or not, there are millionaires and billionaires among us who masquerade as relatively normal, money-conscious people. Take a peek at some of the most frugal wealthy people in the world.Warren BuffettMillions of people read Warren Buffett's books and follow every move of his company, Berkshire Hathaway. But the real secret to Buffett's personal fortune may be his penchant for frugality.Buffett, who is worth an estimated $47 billion, eschews opulent homes and luxury items. He still lives in a modest home in Omaha, Neb., that he purchased for $31,500 more than 50 years ago. Although Buffett has dined in the best restaurants around the globe, given the choice, he would opt for a good burger and fries accompanied by a cold cherry Coke.When asked why he doesn't own a yacht, he responded, "Most toys are just a pain in the neck."Carlos Slim HelúWhile most of the world is very familiar with Bill Gates, the name Carlos Slim Helú rarely rings a bell. But it's a name worth knowing.Slim, a native of Mexico, was recently named the world's richest person -- that's right, richer than the Microsoft co-founder. Slim is worth more than $53 billion, and, while he could afford the world's most extravagant luxuries, he rarely indulges.He, like Buffett, doesn't own a yacht or plane, and he has lived in the same home for more than 40 years.Ingvar KampradThe founder of Swedish furniture phenomenon Ikea struck success with affordable, assemble-it-yourself furniture. For Ingvar Kamprad, figuring out how to save money isn't just for his customers, it's a high personal value. He's been quoted as saying, "Ikea people do not drive flashy cars or stay at luxury hotels."That goes for the founder as well. He flies coach for business, and when he needs to get around town locally, he either takes a bus or heads out in his 15-year-old Volvo 240 GL.Chuck FeeneyGrowing up in the wake of the Depression probably has something to do with Chuck Feeney's frugality. With a personal motto of "I set out to work hard, not get rich," the co-founder of Duty Free Shoppers has quietly become a billionaire but even more secretively given almost all of it away through his foundation, Atlantic Philanthropies.In addition to giving more than $600 million to his alma mater, Cornell University, he has given billions to schools, research departments and hospitals. Loath to spend if he doesn't have to, Feeney beats both Buffett and Kamprad in the donation category, giving out fewer grants than only the Ford and Bill & Melinda Gates foundations.A frequent user of public transportation, Feeney flies economy class, buys clothes from retail stores and does not waste money on an extensive shoes closet, stating,"You can only wear one pair of shoes at a time." He raised his children in the same way, making them work the same normal summer jobs as most teens.Frederik MeijerIf you live in the Midwest, chances are good that you shop at Frederik Meijer's chain of grocery stores. Meijer is worth more than $5 billion, and nearly half of that was amassed when everyone else was watching their net worth drop in 2009.Like Buffett, he buys reasonably priced cars and drives them until they die, and, like Kamprad, he chooses affordable motels when traveling for work. Also, like others on this list, Meijer is focused on the good his wealth can provide to the community.The bottom lineThe little secret of some of the world's wealthiest people is that they rarely act like it. Instead of over-the-top spending, they're busy figuring out how to save and invest to have that much more in the future.It's a habit you might want to consider in order to build up your own little storehouse of cash.Source: SmartbizAfrica