U2's Super Bowl offer to fight AIDS in Africa

Irish rock band U2 has a novel plan of attack for the deadly AIDS epidemic in Africa: giving away music for free.

The band will release its new single, "Invisible," on iTunes as it debuts the song in a commercial during the Super Bowl on February 2.

From that moment, the song will be free to download for the next 24 hours, with an extra bonus. For each of the song's first two million downloads, Bank of America will donate a dollar to (RED), an AIDS charity co-founded by U2 front man Bono. The bank is also pledging a guaranteed $8 million to the charity for a total of $10 million to the fund.

Bono and Bank of America CEO Brian Moynihan announced the partnership from the World Economic Forum in Davos on Thursday.

But then, a small game of viral giving ensured. The Gates Foundation heard about the plan before the news was released and added its support, matching Bank of America's total $10 million donation, dollar-for dollar. Then German software company SAP tacked on a million, as did the the Motsepes, a wealthy South African mining family The total amount of the gift now stands at $22 million.

(Read more: With or without aid, Bono is one with African capitalism)

Since Bono started (RED) with activist Bobby Shriver at Davos six years ago, the $240 million (RED) has raised has gone toward preventing and treating AIDS in eight African countries—Ghana, Kenya, Lesotho, Rwanda, South Africa, Swaziland, Tanzania and Zambia.

(RED) is especially focused on preventing the transmission of the disease from mother to child by 2015, in accordance with UN Millennium Development Goals. Right now, 700 babies are born every day with HIV.

"So we'll have the first AIDS-free generation by 2015 in about four or five countries, it could be 12 countries," Bono told CNBC.

(Read more: Brands plan mega-bashes for next Super Bowl)

BofA's Moynihan had previously invited the rock star to give the keynote address at an Georgetown University's Social Enterprise Institute, which Moynihan supports. Some students were reportedly suspicious of seeing the rock star onstage with the besuited banker, and a few were trying to start an Occupy Wall Street chant.

But, in the end, the pair won the crowd over.

"Though I think the banking community has really let down the world over the last years, some people have tried to stick with values," Bono said of Moynihan.

—By CNBC.com

Correction:

This story has been updated to reflect the correct venue where U2 will debut its song Feb. 2.