Saved for future reference from kottke.org:
the Long Tail of Life: During an 11 month study in 2007, scientists sequenced the genes of more than 180,000 specimens from the Western English Channel. Although this level of sampling "far from exhausted the total diversity present," they wrote, one in every 25 readings yielded a new genus of bacteria (7,000 genera in all).
See also: Venter sequences the Sargasso Sea (and download the dataset here!); a review on the emerging field of metagenomics; genomic databases at NCBI (sequences of everything from the human genome to three strains of ebola); Helicos high-speed sequencing; a nice powerpoint on next-gen short-read sequencing and sequence assembly (including notes on Eulerian walks on De Bruijn graphs, the method used by sequence assembly algorithms like Velvet.) Man, guys, sequencing is the coolest.