Social networking sites like Facebook.com, MySpace.com, Xanga, Bebo and online video sites like YouTube head InternetSafety.com's list of "Top 10 Online Time Wasters.”

But where does most of this time wasting occur?  At work, the Atlanta Business Chronicle reported Tuesday, citing new research by Nielsen Online.

According to Nielsen, the greatest number of Internet videos are watched on weekdays between 12 p.m. and 2 p.m. -- when most people are at work.