It appears E.coli may be useful for something other than tainting food. According to the Guardian, a team of US scientists have engineered a bacterial colony that can be used to solve complex mathematical problems:
The research, published today in the Journal of Biological Engineering, proves that bacteria can be used to solve a puzzle known as the Hamiltonian Path Problem. Imagine you want to tour the 10 biggest cities in the UK - one route might start in London (number 1) and finish in Bristol (number 10), for example. The solution to the Hamiltonian Path Problem would be the route that takes in each city just once.
And here's the kicker:
As time goes by, a bacterial computer will actually increase in power as the bacteria reproduce.