Transit officials say a pilot program has helped reduce garbage inside stations, but results elsewhere have been mixed.
Researchers are using rider data to better understand how stressed subway crowds flow through the system.
When it comes to the Games, the West Coast dominates.
A real-time stream of every photo taken in five cities.
London designers want to outfit the Tube with a real-time scrolling display showing the sky passing by above.
One British designer imagines future office space as symbiotic orchid farms.
London pays tribute to Saturday Night Fever with a party in some abandoned train tunnels.
Forecasters warn that this will be the wettest Summer Games ever, and many venues were not designed for dreary weather.
Po-Chih Lai's "Stair Rover" is meant to conquer the rugged streetscape of London.
"The Majesty" is an installation in an abandoned London railway vault that's crawling with slow-moving, spore-spitting mold.
Artist Stephen Walter maps the city below the surface.
Luke Jerram's wind-powered "Aeolus" looks like the result of smashing together a pipe organ and a porcupine.
A London gardening project aims to plant food up and down a city bus line.
Environmentalists have kicked off a campaign called "Straw Wars" to rid London's Soho district of drinking straws.
Also, a girl can't wear the Confederate flag to prom in Tennessee; the British can't even support their own Olympics; Yertle the Turtle is banned in Canada.
The race to be mayor of London has devolved into personalities, but serious economic and social issue confront the city and its next mayor.
Also outlawed around the world: "gay cure" ads in London, discrimination on the basis of sexuality in Indiana, South Carolina yarn bombing.
Urban explorers recently climbed the tallest building in the European Union. Here's what they saw.
The pinnacle of bus-shelter advertising madness has officially been reached with this pastry-scented campaign in London.