Applebee's - I had a series of visits with absolutely horrible service in Jacksonville, NC about a decade ago and haven't been back to any of their locations since
Susan G. Komen - When my mom was diagnosed with breast cancer about 15 years ago and we wanted to make some donations we looked up their financials and realized that they spend a HUGE amount of money on advertising, relative to what they spend on research. They are also bully's who have copyrighted doing something "For the Cure" and are attempting to copyright the color pink and are very litigious towards other, often more reputable, non-profits. Our money goes to a specific hospital and university research programs instead.
Boy Scouts of America - I do not agree with their efforts to exclude homosexuals (however, if I had a son, and he wanted to join the Boy Scouts, I would voice my concern but probably not stand in his way).