MicrobeWorld

"Synthetic biology has already delivered engineered organisms that can churn out a malaria drug, cook up an ideal biofuel or act as biosensors, but questions remain about how such organisms can be eliminated from the environment after they have performed their task.

A team of US biotechnologists now thinks it has the answer: gene networks that can count. Endowing cells with this ability could lead to strains with a programmable shelf life, they say."

This is some pretty interesting stuff, especially if you consider the fears and suspicions surrounding synthetic biology.