A vigorous marketplace works best when buyers are equipped with information. According to a recent article in the New York Times, health care consumers are acquiring more information every day.

"At least three-quarters of all Internet users look for health information online, according to the Pew Internet and American Life Project; of those with a high-speed connection, 1 in 9 do health research on a typical day. And 75 percent of online patients with a chronic problem told the researchers that “their last health search affected a decision about how to treat an illness or condition."

The article warns that if you rely simply on Google, you may be missing a lot if you're not careful. Adding the word "community" with the name of a condition, for example, may bring up a host of resources that let you learn from other patients, such as PatientsLikeMe.com.

Even apparently frivolous applications, such as Flickr (photo sharing) and Twitter (the online equivalent of short text messages) can be useful in managing one's health, the article points out. But "Can online information be trusted? The answer, increasingly, is yes."

Other types of sites include:

General interest sites, such as WebMD.

Sites featuring medical research results, such as PubMed.

Disease-specific sites, such as Diabetes Mine.

Tools that help you manage your condition, such as Destination Rx, for comparing drug prices.