Meme theorist Susan Blackmore has a great article up at New Scientist about memetics and the possibility of a similar replicator that spreads not brain-to-brain but machine-to-machine. Basically...well, it's probably better if you just click the link and let her explain it. She also has a great talk on the subject up at TED (lots of great stuff there; check it out).

Oh! Oh! And I found an illuminating Q & A with her from WIRED last year.