One of the best Craigslist ad ever:

I SERVED 17 YEARS IN THE NEW JERSEY PRISON SYSTEM. I AM A REAL GENUINE THUG. I HOWEVER, TURNED MY LIFE AROUND AND I NOW OFFER MY SERVICES TO HELP TROUBLED TEENS. I CAN TELL ANY PARENT WITHIN 2 SESSIONS IF THEIR CHILD IS WORTH WHILE OR IF THEY WILL END UP IN PRISON. I DO NOT YELL OR SCREAM, I WILL SHOW THE TROUBLED TEEN THE REAL WORLD AND WHERE BAD BEHAVIOR WILL SEND YOU. TRUST ME, I AM GOOD AT THIS. WHAT DO YOU HAVE TO LOSE EXCEPT YOUR CHILD’S WELL BEING AND YOUR PIECE OF MIND.

http://cnj.craigslist.org/sks/1446740665.html