Americans donate $8M to national debt

(CNN) — Are you looking to donate money to a good cause? Would you consider volunteering to pay down the national debt?

Americans have donated nearly $8 million of their own funds this year to help reduce the nation's $16 trillion (and growing) credit card bill.

Although it's a tiny fraction of the overall debt, the amount donated this year has doubled over last year.

The idea of donating to the national debt began in 1961 when an anonymous estate left $20 million to the Bureau of Public Debt. Congress then passed a law to accept those funds.

Today, citizens can contribute online at pay.gov, or include an additional check with their federal income tax returns.