I just wrote the following snippet of code for my dissertation:

intNatI :: Int :~= Nat
intNatI = Iso {
            to   = fromInteger . toInteger,
            from = fromInteger . toInteger }

The components to and from have totally different types (to is Int -> Nat, from is Nat -> Int). Yay for type inference! :)

The title of this entry (if you take "buffalo" to be 1) the obvious noun with identical plural, 2) capitalised, the proper noun referring to the American city, and 3) a verb meaning approximately "bully") is a grammatically correct sentence of English. (I first came across it in The Language Instinct by Stephen Pinker, but was reminded of it recently.) In fact, according to Wikipedia, for any n ≥ 1, buffaloⁿ is a grammatically correct sentence, if you disregard capitalisation. ("Buffalo!", "Buffalo buffalo", "Buffalo buffalo buffalo", etc.) Don't you just love natural language?