Reversing the Lens: Sexual Harrassment Victim uses social media, leads to harasser's arrest 1 Favorite 

 A young woman named Thao Nguyen was riding the R train in NYC when a man sitting across from began to masturbate. Nguyen snapped a picture of him, but the policewoman to whom she reported the incident had little interest in the photo.  Nguyen uploaded the shot to her flickr set with a description of the internet.  From there, social media carried the incident, and the photograph, all the way to the front page of the Daily News.  After the paper ran, the man was apprehended.

This spontaneous action was notable because it utilized emerging medias (camera phones and online photo-sharing) for social justice.  It inspired a public blog and smartphone app, Hollaback!, to continue the conversation, raise awareness, and attempt to end street harassment.  Hollaback! documents street harassment, empowering
objectified victims and inspiring allies in an effort to end the
attacks. 

From their website: "Hollaback! is a project dedicated to combating a particular form of violence that designates subordinated groups (such as women and LGBTQ folks, for example) as targets in public spaces or otherwise vulnerable to unsolicited, nonconsensual encounters with strangers." Hollaback! is currently active in approximately 50 countries in 18 countries.