ooooooooooh.

c'mon! c'mon! teach them to kill!
we're tantalizingly close to things going horribly wrong.
ooh! ooh! maybe some good samaritan type scientists will have them innoculate people in africa. they can do it in no time, for low cost, etc etc...also, they can evolve and create a race of zombies!

http://www.dailytech.com/Robots+Swarms+Learn+to+Communicate+On+Their+Own/article6242.htm