On craigslist, at least US locals, they have a section called "rants and raves" that is a sounding board for people. The one here is has nothing but people fighting back and forth with some pretty nasty stuff. Example one guy who was fired as a school bus driver constantly posting about how the company 'wronged him' and how many ads they have. Some guy bragging how he flattens tires of non American vehicle in parking lots. Lots of racist garbage. Etc. Basically stuff posted that would get someone popped in the face if they said it in person but since its totally anonymous, they get brave.