Kiva.org allows individuals to make $25 loans to low-income entrepreneurs in the developing world (microfinance). By doing so, individuals provide affordable working capital for the poor (money to buy a sewing machine, livestock, etc.), empowering them to earn their way out of poverty.
It's a new, direct and sustainable way to fight global poverty, and the way I see it, I get a higher return on $25 helping someone build a future than the interest my checking account pays.
If you have a minute, please check out the site: http://kiva.org. If you need more "reputable" validation than my recommendation , know that they have received great press in publications ranging from The Wall Street Journal to NPR to BusinessWeek.
All the money you donate goes straight to the people who need it - if you can spare just $25, it's really an easy way to help people who are trying to get out of poverty in other countries.