1. Submitting to directories will increase your PR. Andreiuk, who cares about PR if you have no traffic, even if you have PR10 and no visitors how do you benifit? 2. Submitting to well known directories is good but being on page 100+ will not really help, not sure if SE's will find those pages ever, thus it's either paid inclusion or new directories (if you get lucky with new directories and in a few years time they'll become more prominent).