From MSNBC:
Bacteria have been programmed to behave like computers, assembling themselves into complex shapes based on instructions stuffed in to their genes. The work was led by Ron Weiss, an assistant professor of electrical engineering and molecular biology at Princeton University. The research could lead to smart biological devices that could detect hazardous substances or bioterrorism chemicals, scientists say. Eventually, the process might be used to direct the construction of useful devices or the growth of new tissue, perhaps restoring function to a severed spinal cord.
The study is detailed in April 28 issue of the journal Nature.
More here.