When electricity was new, town leaders looked to "moonlight towers" to provide mass illumination.
Hard science is finally backing up centuries of aromatherapy wisdom.
They're not just for hippies anymore.
The people and ideas reshaping urban life
Base price: $1.3 million.
This device to "see" people trapped behind flames also makes them look supremely creepy.
The Mu Thermal Imager, which detects drafty doors and windows, aims to be an affordable device for improving your home's energy efficiency.
Publicly owned Internet infrastructure is luring jobs to smaller towns. Should big cities follow their lead?
The high-tech billboard transforms atmospheric moisture into drinking water for thirsty Peruvians.
The odd vehicle, which transforms old coffee grounds into hydrogen, recently set a Guinness land-speed record.
Should the title of Most Boring City Simulator go to garbage collection, toilet cleaning or European bus driving?
Studying the emissions of megacities like Los Angeles promises to be the next big thing in combating global warming.
Contour lines borrowed from natural terrain can tell us much about life in the city.
Critics of London Mayor Boris Johnson's ambitious air pollution plan may be missing the bigger picture.
A ban on outdoor gas heaters from Parisian cafés doesn't look like it will be implemented anytime soon.
Projects from Vancouver to Washington to Kathmandu.
Five winners will be announced this spring, but these ideas stand out above the rest.
5 percent of Tweets out of the city are in a language other than English.
Take on the role of violent agitators or the police in this atmospheric smartphone simulator.