Trailfire is a free service and is described as a way to let bloggers place multimedia rich comments on any Web page and automatically link related Web pages to form a trail, or navigation path. The product is a download plugin for Internet Explorer and Firefox. Interestingly, they claim it is “more complementary than competitive” with social bookmarking sites. They reckon that a ‘trail’ is a topic and Trailfire does not support tagging – whereas social bookmarking sites are used to categorize web pages with tags, but do not support trails/topic mapping. If this concept sounds familiar, it’s because Internet pioneer Vannevar Bush used the term “trails” in his influential essay from 1945 called As We May Think.