Computer science is probably not going to blow up the world any time soon. The greatest threat from computer programs is to personal privacy. Computer camera's that can read your emotions, cellphones that can track where you are 24/7, online databases that store your online browsing, governments that look through your email, and then I haven't even started with the crackpot theories.
I experienced a good/bad moment not too long ago in my scientific research when I was doing research on the effect of the TPB website blockade on BitTorrent use in the Netherlands. Everyone knows that it had 0 effect, but you have to prove it. So in one afternoon I built a script that could scrape peer-lists, and did some analysis on those.
The evilness of this script is that it can just as well be used by the movie/record industry to easily find out who's downloading. It's not groundbreaking, and they could probably build it themselves too, but still, this gets you thinking about the possible evil use of other research.