I know everything about my log files (extended log files). We use "Web Trends" analyzer: I know the number of users arriving from banners, links, search engines etc. We have statistic about the orders we receive; we receive orders through a form on our web site. How can we know exactly how profitable is each banner, link or search keywpord or phrase? Our pages are in solely simple HTML (we do not use ASP). I know that maybe it could be possible to monitor this profitability using cookies.