On many websites you will see a small links button to a directory of websites. The important factor here is to make the link partners chosen relevant to the subject matter of the website. Arbitrary linking to websites not connected, or not a resource that the website users would benefit from, is not recommended as this is where the phrase 'linkfarm' would sneak into the picture.

Another consideration with search engines like Google is the aspects they place on ranking a page in conjunction with backlinks. A backlink from a website that has a high page rank is positive, conversely a backlink from an unknown, virtually unlisted website, has a negligible affect on the listing. One option is to have lots and lots of negligible backlinks, or secondly you could seek out and possibly pay money (or display flashing advertisements) for links from highly ranked websites. The downside of the first option is that you would have to virtually turn a section of your website into a full blown web directory, or have lots of advertisements. Both of which could be considered detrimental to the integrity, point and visual appeal of the website.

Basically legwork has to be done to find high quality useful website links.