The scariest thing I've seen in the past few years was that "artwork" with a culture (I think it was E. Coli but it might have been staph) growing on a large sheet of agar which had been doped with a gradient of various antibiotics, and showed the bacteria slowly adapting and working its way through them. A small change to this setup could easily be used to grow multi-antibiotic-resistant diseases in someone's back shed. I actually kind of don't want to post this comment in case it gives someone ideas.