Shel Horowitz, author of Principled Profit,  Grassroots Marketing, and The Penny-Pinching Hedonist, has co-authored (along with  Jay Conrad Levinson)  Guerrilla Marketing Goes Green.  Combining  simple but ingenious viral marketing strategies with environmentally and ethically responsible principles, the  book shows you how to harness and multiply social connections to increase profits and do good at the same time.