You must read this:
“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 known to exist since 1972 when the sentence was used by William J. Rapaport, currently an associate professor at the University at Buffalo.
via Charlie in Colorado.
You can have fun for hours, reading out the URL to people down the phone. No cheating via TinyUTL and the like.