Gladwell compared the level of commitment in online communities to the real risk taken by Freedom Riders and sit-in participants in the American Civil Rights Movement.

FORBES: Action is the True Measure of Engagement

The Digital Public Library of America began beta testing Thursday, promising a site with millions of materials ranging from images of George Washington to footage of Freedom Riders during the civil rights era.

WSJ: Digital public library with vast archive opens

Ms. DICKSON: A group of freedom riders had come to town in August of 1961, and although Rob wasn't participating with them because he would not take a position of being passive when it came to resistance, he was supporting them, offering them housing, transportation.

NPR: 'Negroes with Guns': A Radical Battle with Racism

My mother wrote letters to my father in the summer she rode with the Freedom Riders, and you know, I think that even as she might have imagined such a moment, I don't know if she would have believed that it could occur in her lifetime.

NPR: Natasha Trethewey: If My Mom Could See Us Now