Americans set a new record for generosity last year. We gave a total of nearly $300 billion. But few of us could match the generosity of Richard Semmler.

Semmler is a 61-year-old math professor at Northern Virginia Community College. He's also a maintenance man, and a book editor. His hard work earns him more than $100,000 per year, but he lives very modestly.

Even with three jobs, Semmler lives in a tiny apartment. He's not working so hard to get more — he's working to give more. Semmler has donated nearly $1 million — between 50 percent and 60 percent of his income each year — to six charities, and his money helps to feed the homeless and build houses for families in need.

Semmler's not just writing checks — he's getting his hands dirty, building those homes with Habitat for Humanity, and handing out food in soup kitchens.

"I prefer to live in a small apartment. I prefer to drive an old car," he said. "I get a lot of satisfaction out of that. I get a chance to see my dollars at work.

"For me, it's a personal satisfaction in seeing the house built, but more important, it's personal satisfaction in seeing a family that truly needs this," said Semmler.

Semmler belongs to a very exclusive club that anyone can join. It's called the Fifty Percent League. Members give away at least half their income to charity. Not all of the donors have big incomes. One woman earned just $16,000 dollars last year, and gave half of it away to help newly arrived immigrants.

The group is made up of about 100 people and growing. Collectively, they have given away more than $1 billion over the past decade, donating to all kinds of charities, from cleaning up the environment to cleaning up the inner cities.

The Fifty Percent League was the brainchild of Chris and Anne Ellinger, who decided to give half their money away when they came into an inheritance.

"I remember feeling anxious beforehand — are we going to regret this afterward?" Chris recalled. "I look back on it as one of the best decisions we ever made.''

Even actress Angelina Jolie reportedly gives away a third of every film paycheck she receives. This weekend, she's supporting a children's health program in New Orleans.

But you don't need a film star's income to make a difference. The Ellingers say you don't have to give until it hurts.

"We're definitely not saying people should be giving at 50 percent. We're just saying figure out what is your true potential," said Anne. Her husband Chris added, "We encourage people to start making a financial plan, and figuring out what are they going to need, and look at what's left over.

"Just about everybody said it was one of the most joyful acts of their lives."

"What's an issue that you care most about, and what difference do you want to make," Anne said.

Millionaire David Ludlow is a fifty-percenter, who funds an after-school program in Boston's inner city. "This has made me a truly happy man, being able to do this. It's been magnificent. It's totally turned my life around," Ludlow said.

And can money buy happiness? "Yes, yes it can," Ludlow laughed.

Semmler believes the effort is all worth it. "There are a few personal sacrifices, it means very few vacations, and it means working many extra part-time jobs to make this all happen."

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