I had a chili pepper on Rate My Professor once. It was removed after grades were handed out.

My favorite was evaluations. "Ms. K is fabulous, I love the way she incorporates lessons about the culture" "Ms. K is awful, I wish she'd stop talking about culture and just focus on grammar"

Not sure what to do with feedback like that.

When you get more professional you learn how to be twofaced in a more professional way. Never leave things in writing where the defamed person can figure out who you are and take revenge. Also, having a paper trail makes credible slander more difficult. People recognize the pattern and style and then discount it. Use fallible memory to your advantage when climbing the corporate ladder.