What is a Google Bomb?

According to Wikipedia, “A Google bomb or Google washer is a certain attempt to influence the ranking of a given page in results returned by the Google search engine, often with humorous intentions. Due to the way that Google’s PageRank algorithm works, a page will be ranked higher if the sites that link to that page all use consistent anchor text. A Google bomb is created if a large number of sites link to the page in this manner.”