Worried that embalming fluids or emissions from cremation will pollute the earth after your death? There may be a more eco-friendly albeit somewhat grisly alternative—dissolving the body in lye. The process, which has been used to dispose of animals and lab specimens for many years, is now being considered more seriously for human use. Called alkaline hydrolysis, the method uses a steel cylinder that dissolves the body in lye with 300-degree heat and 60 pounds of pressure per square inch. The result is a sterile, coffee-colored liquid with the consistency of motor oil that can be safely poured down the drain. A small amount of bone residue that can be scattered like cementation ashes is the only solid byproduct.

Hanyoung Lee wants you to be seen. The South Korea-based product designer devised a prototypical warning device to prevent pedestrian strikes along roadway crosswalks. It's called the Virtual Wall, a visual barrier created from plasma laser beams.

Modern air travel is a marvel. It's also a source of endless delay, annoyance and planet-killing greenhouse gases. A proposed hydrogen-powered hypersonic airliner could change all that. The plane is Reaction Engines's A2 concept, a Mach-5 (3,400mph) craft for 300 passengers funded in part by the European Union's Long-Term Advanced Propulsion Concepts and Technologies project (Lapcat). Lapcat wants an airliner that can fly from Brussels to Sydney in less than four hours. If built, the A2 will do just that—without producing a trace of carbon emissions.