Remember, people search two ways. They'll either use keywords, or comb through categories in a directory. The keyword results are generated from a combination of paid placement words with words programmatically culled from most of the sites on the Web. Category listings, on the other hand, are built by a group of human editors.
There are now three primary teams of editors out there trying to organize and categorize the general web: Yahoo!, DMOZ, and Zeal. The editors on staff at Yahoo! build their directory exclusively for Yahoo! DMOZ (dmoz.org) is a well organized group of unpaid editors that have built an impressive directory, called the Open Directory Project or ODP, that almost every other search site utilizes including AOL, Netscape, Google and Lycos. Zeal is a similar collection of volunteer editors categorizing only non-profit sites for inclusion in LookSmart's otherwise paid directory, used by a number of search sites, including MSN.
DMOZ, short for Directory Mozilla, is administered as an open source community by Netscape. There is no charge for site submission to the Open Directory from DMOZ, just as there is no charge to the portals and search sites for use of the entire catalog. The taxonomy of sites is especially good because the community of editors is so vast, with each editor specializing in a topic area suited to his own expertise. And, that vast community of editors allows for a significant number of sites to be added on a regular basis.
In addition to buying keywords and crafting search-robot friendly sites, submitting your brand's site to the two commercial editorial teams, Yahoo! and DMOZ, should ensure your site’s inclusion in most user's search results - no matter how or where they search.