Check 'Em Out on MySpace Social networking sites spark unofficial background checks.

When Tim DeMello is hiring, he visits popular social sites like MySpace and Facebook to see what, if anything, applicants have posted there.

Searching for someone's online footprint from the comforts of his office is quick and easy, says DeMello, 47, founder and CEO of Ziggs, a 2-year-old, 15-employee Boston company that runs an online search directory and community for professionals. It's also cost-effective. Online searches can save entrepreneurs the money they would invest in a traditional third-party background check. And they help entrepreneurs sketch an applicant's character.

Employers can reject applicants based on what they find, and they don't have to tell applicants why they were rejected or even that an online search was done. Some job seekers are learning about the perils of online journaling the hard way. DeMello was shocked recently to find that an intern divulged on Facebook that his workday consisted of "screwing around on IM" and "talking to my friends and getting paid for it." DeMello showed the entries to the intern, who fessed up and was fired.