In February 2000, Amazon announced that it had been granted a patent on components of an affiliate program. The patent application was submitted in June 1997, which predates most affiliate programs, but not PC Flowers & Gifts.com (October 1994), AutoWeb.com (October 1995), Kbkids.com/BrainPlay.com (January 1996), EPage (April 1996), and several others.
Note: I think the line where readers will push back probably will vary from blog to blog depending upon their readership. For example here on ProBlogger I get a little more negative feedback from readers on affiliate promotions. I suspect ProBlogger readers are a little more tuned into the issue and suspicious of some of the affiliate marketing that goes on around the web.
By quite a large margin Amazon has the largest affiliate marketing program out there, with products from more than 1.5 million sellers. Amazon has the most easy-to-use technology of all the affiliate programs I will be reviewing today. Beginners to affiliate marketing with even the most limited technical expertise will have no problems in getting up and running with the Amazon associates program, while more experienced marketers can create custom tools and websites with the APIs and advanced implementations available to them. The great thing about Amazon is that anything from kids toys to laptops can generate sales if they are purchased through any Amazon affiliate link.