I've been meaning to write about Intuitive Systems, a company formed by an old friend Dave Taylor I used to hang with back in the 1980s when I first moved out here. (figmo, you probably remember him from some of those kabuki-west dinners where arguments about the bill led some people to ask for separate checks at future dinners.) He's been active in a number of different areas: e-commerce startups, how-to books on computers and the Internet, education, and now blogging. He used to describe the type of business that he wanted, and the type of impact he wanted to have on the computer industry, and it seems he has been able to accomplish all he wanted.
In his Q&A blog, AskDaveTaylor, one can ask him questions on a variety of topics, including PPC advertising. He is aware of click fraud but seems to be fairly positive about the PPC model.