It gets its directory information from the Open Directory project. In addition to being a stand-alone service, LookSmart provides directory results to many other partners. Lycos - Lycos' main listings come from the Open Directory project, and then secondary results come from spidering the web. Lycos also features another directory of web sites called Lycos Community Guides. Lycos is one of the oldest search services, around since May 1994.
Search results are good, but there's no related search feature.
Secondary results come from Google. At the Netscape Netcenter portal site, other search engines are also featured. Here's a FAQ about searching with Netscape Navigator. Northern Light - Another favorite search engine among researchers. It features one of the largest indexes of the web, along with the ability to cluster documents by topic.