[dchichkov]

It seems like it would be much easier to finally make some self-replicating bots, or just self-repairing bots, or even just a small factory that can produce bots... And leave it there for a couple of decades with the task of writing that 'hello' message.

[yzzxy]

Cellular automata sent to billboard the moon would be a great concept for a sci-fi short story.