This page shows a very cool trick for anyone wanting to diversify their link profile. This trick shows you how to instantly get thousands of high page rank backlinks using a php hack. The basis of this backlink trick are several, specialized Google searches that turn up web pages that are vulnerable to this trick.

The web pages that turn up use a php file to store links to numerous web pages, both internally and externally. All of the urls redirect to the desired links via a query string similar to php?q=http://www.websiteurl.com. You simply replace http://www.websiteurl.com with the url you want to redirect to ...