http://www.google.com/technology/pigeonrank.html

As a Google user, you're familiar with the speed and accuracy of a Google search. How exactly does Google manage to find the right results for every query as quickly as it does? The heart of Google's search technology is PigeonRank™

Building upon the breakthrough work of B. F. Skinner, Page and Brin reasoned that low cost pigeon clusters (PCs) could be used to compute the relative value of web pages faster than human editors or machine-based algorithms.

And on a side note, the RFC Spec for A Standard for the Transmission of IP Datagrams on Avian Carriers
http://rfc.sunsite.dk/rfc/rfc1149.html