I list my websites on this FORUM all the time. The main one is www.subclub.org.

Some of the links are pretty obvious -- ads that have nothing to do with subminiature photography (see the bottom of the main page). Other are pretty hard to fine. Some SEO companies pay me to ad a link to a particular word on an obscure page -- such as the word "diamond" on a page about a Kodak camera.

But you have to understand that I did not seek out these SEO companies. They contact me because my website is VERY old and it's VERY obscure (submini photography) and it's on the top of the GOOGLE list for its topic. For these three reasons (and perhaps others), having my website link to another website bumps the other website up the ladder (supposedly).