Fun anecdote -- in the late 90s I maintained several web sites (personal/hobby ones) and by far the best source of traffic for them was Yahoo directory pages. I didn't know the SEO game (if there was even one at the time) and while search engines brought a small amount of traffic, majority of visitors came from Yahoo. When I launched a new hobby site, the goto marketing plan was to apply to add it to Yahoo. Granted, we're talking about the range of dozens to maybe a hundred or two visitors a day, so it's not web scale :)