Googlebombs

A Googlebomb (or linkbomb as they not only affect Google) is basically a prank where people try to cause someones site to appear high in the SERPs for some weird or obscure keyword or phrase. Usually this works with uncommon phrases as there are not a lot of sites that have been optimized fo these phrases. It is done by getting many webmasters to link to a certain website with the obscure phrase in the anchor text. One of the first Googlebombs was for the phrase "talentless hack".

Google just recently announced they have altered their algorithm to filter out Googlebombs (in any language).