Posted by Andrew VanderPloeg
And now...from the files of "Just because you can, doesn't mean you should":
"'Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo.' is a grammatically correct sentence used as an example of how homonyms and homophones can be used to create complicated constructs. It has been discussed in literature since 1972 when the sentence was used by William J. Rapaport, an associate professor at the University at Buffalo."
Check out the full wiki here.