Russian Alexander Tretyakov hits the padding at the end of his second heat in the Men's Skeleton during the Vancouver 2010 Winter Olympics in Whistler, British Columbia, on Feb. 18.
The Philadelphia building collapse that killed six and injured 14 happened as the building was being demolished. Eyewitness accounts offer clues into what might have gone wrong.
A national campaign to brand the Tuesday after Thanksgiving as an annual day of giving is a product of the digital age, steeped in social media, with its own Twitter hashtag: #GivingTuesday.
While the ability to track 'flash mob' lawbreakers on Twitter and other social media platforms offers a powerful, futuristic vision for policing, real-life police response has so far been more Sherlock Holmes and less Blade Runner.
The crackdown on 'flash mobs' by Philadelphia Mayor Michael Nutter has put him in the center of a debate about how black leaders should respond to violence within their own community.