A team of celebrities are taking part in a challenge to raise funds for a charity of their choice. The Mozilla Firefox Challenge is being taken by Christy Turlington Burns for Every Mother Counts, Jason Bateman for City Year, Sophia Bush for F Cancer, Zooey Deschanel for the Innocence Project, Paul Rudd for the Rolling Dog Farm, Barbra Streisand for the Women's Heart Center at Cedars-Sinai Medical Center, Edward Norton for the Maasai Wilderness Conservation Trust, Will Ferrell for Cancer for College, David Blaine for charity:water, Seth Rogen for The Alzheimer's Association, Jonah Hill for Nothing But Nets and many more. Christy is offering fans the chance to win signed t-shirts, CDs, DVDs and a personal chat via Skype in return for donations. Mozilla Firefox has promised to award $25k to the charity that raises the most money by January 11.