What is the best way to tarnish the reputation of a business that has wronged you?

If I was feeling how you are.....I would make a big sign that I could wear that says something like "don't do business here...you'll lose your shirt" or something along that line.Then I'd take some holidays and picket their shop.They might just try to make you happy, to get rid of you!Good luck,I hope it works,whatever you do :)