Taz

Genome sequencing has come a long way since the Haemophilus influenzae, the first bacterium to be sequenced, had its hereditary pants pulled down in 1995.  Since that time, nearly 200 organisms have been sequenced.  Certainly most would point toward Homo sapiens as the most significant of these, I'm going with the Tasmanian devil.

Interesting, and disturbing, sidebar to this story is the devil's extinction threat rising from a contagious form of cancer known as Devil Facial Tumor Disease.  The concern that low genetic diversity might be related to the spread of the disease was one factor motivating the genome sequencing project.