Raining oil in Louisiana: A YouTube video claims that oil is falling from the sky in a New Orleans suburb. Here's why this is almost certainly not true.
The US is a late entry, but new domestic projects are revving to go.
Readers write about ethanol, subway "smart card" security, and potatoes.
Scientists look for technologies to push particles faster, better, and cheaper.
A third major group, whose materials work at relatively high temperatures, may lead to more efficient electric motors.