The Roman poet Horace once said of his works that "I have created a monument more lasting than bronze." Well, Canadian poet Christian Bök has pretty much blown Horace away with his plan to encode a poem into bacterial DNA.
The plan is simple enough, if completely insane. Bök hopes to inject a series of nucleotides into the DNA of the bacteria Deinococcus radiodurans that form an intelligible poem, and then, in case that was too easy, he wants the protein the bacteria manufactures to also form a meaningful poem.
Since he only has four characters to work with - the nucleotides adenine, cytosine, guanine, and thymine - he first needs to create an alphabet that substitutes various triplets of nucleotides in the place of the twenty-six letters. In other words, AGT might correspond to "a", while CTG could mean "b", and so on. However, Bök can't just choose the triplets at random, because for all the trillions of possible combinations, only a minuscule fraction will produce amino acids that also yields a workable vocabulary.
Bök is currently using specially designed software to find the optimal arrangement, and only once he's figured that out will he actually write the poem. He has said that he will be somewhat limited in what sort of poetry he can write, and that most likely he will compose something with a "repetitive, incantatory quality."
Once all that's done, it's up to lab technicians to string together the right nucleotides and inject them into Deinococcus radiodurans. It won't be easy and may take several attempts, but the potential legacy of such a project is almost incomprehensible. If Bök's poem nucleotides take hold in Deinococcus radiodurans, there's no reason to think they won't hang around for the lifespan of the species.
And considering there's also no reason to think this strain of bacteria will ever go extinct (or at least last until the Sun destroys the Earth five billion years from now)...well, there's an excellent chance that Bök's poem will eventually be the last evidence of humanity's existence left on planet Earth. I imagine Horace would approve.