Submitting to web directories will therefore have two massive benefits for your website: the first is that your website will get direct, targeted traffic from the directories themselves, secondly your website will obtain a good quality, one-way link from every directory you submit to, this will drastically improve your search engine rankings and Google PageRank®, often moving your website many pages in the search engine results. Because according to the experts, "One way links carry more weight in a search engine algorithm than swapped links". However, combining the two will increase your "PR" much more.
So, if you're having a hard time driving costumers to your site, here's a list of 100 Free Web Directories, courtesy of Basicxpressions. Happy Submission!