This website offers a rough gauge of the carbon-dioxide emissions associated with flying around the country. Just plug in a starting point and destination and it gives you a round-trip estimate of the greenhouse-gas "footprint" of your travel. The goal is to encourage visitors to buy carbon-offsets to cover the greenhouse-gas cost of their treks. But you can play around for free, testing various travel scenarios. The game can't help but open one's eyes to the usually hidden cost of travel-related emissions. Other pages on the website allow you to calculate the carbon costs of travel by guests ...

One sound that characterizes American summers is the cicada chorus. The insects' long, drawn out serenades can be loud and ethereal, reminiscent of some cross between the sounds of rustling and scraping. Half a world away, Borneo's cicadas belt out very different melodies. Although some sound fairly familiar, one available at this German site is almost characteristic of the screeching soundtrack typical of a grade-B science fiction movie, just as the alien is arriving. A link will transport visitors to another site with dozens of Japanese cicada tunes.Go to: http://www.groms.de/data/zoology/ri...

The University of St. Andrews, in Scotland, has developed some face-transforming software that allows people to change the age, sex, or ethnicity of the person in an image that you export from your computer. Or, blend features from a number of faces into one amalgam. If all that is too creepy, then just import art or animal images and morph them.Go to: http://www-old.cs.st-andrews.ac.uk/~morph/fof/index.html

Polyclad flatworms are soft, juicy, and delicate coral-reef dwellers. To avoid predation, many have evolved brilliantly hued coloration. It’s a trait that often signals a critter is toxic, as many of these worms indeed are. Alas, their bright skins are likely not well appreciated by members of their own species, owing to very poor eyesight. Learn more about these pretties and view spectacular examples at Marine Flatworms of the World.Go to: http://www.rzuser.uni-heidelberg.de/~bu6/index.html

Mention rust, and most of us think of the oxidized metal that signals the aging and decay of cars, fences, and bolts on the backyard deck. However, many plants also suffer from rust—in this case, fungal diseases named for their characteristic reddish-orange color. With a particularly virulent example known as Ug99 (see Wheat Warning—New Rust Could Spread Like Wildfire) poised for a potentially global epidemic spread, consumers would benefit from a greater appreciation of the havoc these pathogens can wreak. The Agriculture Department's Cereal Disease Laboratory offers a site where on...

Members of an established ecosystem develop a sense of balance, usually permitting at least limited biodiversity and a stable structure. When interlopers arrive that aren't responsive to the same environmental checks and balances, they can overrun the ecosystem, eliminating some members and quickly dominating others. Such bullying immigrants are known as invasive species—and they can be newly introduced garden plants, fish, insects, trees, worms, even fungi. The U.S. Department of Agriculture offers one-stop shopping for news and impacts of such invasive species.Go to: http://www.invasive...

With continuing concerns about the decline of honeybees in North America—and especially the newly recognized Colony Collapse Disorder—here's a site to learn more about the important role these and other bees play in plant health and agriculture. This academic site links to plenty of related places on the Web that also address threats to not only bees but to pollinators generally.Go to: http://www.oardc.ohio-state.edu/agnic/bee

Our Food For Thought column recently published two offerings on health-related findings about genistein, a soybean constituent. Ever wonder what that chemical looks like? Or how about capsaicin—the spicy agent in hot chilies being explored as a painkiller, lycopene—the red pigment in watermelons that may protect our skin against harmful ultraviolet rays, or sulforaphane—a trace constituent of broccoli that can turn on enzymes that may help prevent cancer? Florida State University microscopists have created a dazzling image gallery of these and other purified dietary phytochemica...

Although computer programs can be written to sort galaxies into general categories, they would inevitably throw out the unusual, the weird and the wonderful, astronomers say. Because the human brain is much better at recognizing patterns, astronomers launched a site this week recruiting the public to help identify spiral galaxies on sky photos. Instructions are offered on the site. The first million viewers are promised to see a portion of sky never before witnessed by human eyes.Go to: http://www.galaxyzoo.org

Sawfish will soon be getting United Nations protection from exploitation. Right now, the only U.S. state where these ancient fish can generally be found—and then, only rarely—is Florida. Here’s a site to view the fish, a member of the shark family, and link to research aimed at rescuing populations of its seven beleaguered species worldwide.Go to: http://www.floridasawfish.com