Most of us have done it. We've posted a picture to our Facebook profiles and tagged a friend, and that picture doesn't exactly show the friend's best side. Sometimes it's a drunk photo, sometimes it's goofy, and sometimes friends just don't like it and say, "Why in the world did you post THAT? My hair isn't right. I look fat. I don't have makeup on. Thanks a lot."

A few months ago I was at a face-painting party and this devilish photo ended up on Facebook. It's not an awful pic, but it's not an everyday look and showcases the large forehead that I work so hard to disguise. (Or as Al Mack would say, a "fivehead.")

How many female Facebook users admit to posting unflattering photos of their friends?

A survey of 1,500 women by the website MyMemory says 25 percent of female Facebook users admitted posting ugly pictures of their friends.

When that happens, most people untag themselves from the offending photo, but the original photo usually sticks on the original poster's page. Would you request that your friend remove it completely? I'm sure it depends on the content. If you're half naked and happy on margaritas, you'd probably request it be removed before your boss sees it.

Two-thirds of survey respondents said they would be angry at a friend who posted a bad picture. Maybe that friend doesn't think it's a bad picture? We are our own worst critics after all, and sometimes friends don't think we look that bad.

Sometimes it's revenge to post a bad picture. In about one-third of all unflattering pictures being uploaded on Facebook it's for revenge. How devilish!