"The Millionaire Next Door" by Thomas J. Stanley and William D. Danko

First published in 1996, "The Millionaire Next Door" distills Stanley and Danko's findings from more than 20 years of research into seven key characteristics that explain how the elite club of America's millionaires became rich.

Why it's great for young people:

"'The Millionaire Next Door' is great for people in their 20s because it talks about the basics of personal finance," says Rob Gough, co-founder and president of Eckim (DefinitiveDeals.com, CouponChad.com). With simple, commonsense lessons like "spend less than you earn," "avoid buying status objects," and "diversify your investments," the book helps readers develop good habits from the very beginning.