Black Light Glowing Pigs [UPDATE: that link is almost 5 years old and no longer works]
Genetic material containing a fluorescent jellyfish gene was inserted into pig cells grown in a laboratory. Nuclei from these cells were then placed inside donor pig eggs whose own DNA had been removed.

Five eggs were implanted into the womb of a surrogate mother pig which gave birth to a litter, labelled NT (nuclear transfer) one, two, three, four and five, in March. Four piglets had yellow snouts and hoofs which glowed when placed under an ultraviolet lamp. (via Bitstream)