AltaVista and HotBot for me. Yahoo wasn't a search engine, it was a manually curated website directory (with a hierarchical structure), which was great for finding similar websites if you found one you liked.

You could get search results on yahoo. The directory results would come first and then search results from their current “partner.” At one point it was Inktomi, the Berkeley company behind HotBot. At one point it was Google. Before them, one of the more generic ones.