This has got to be the most bizarre movie-plot threat to date: alien viruses downloaded via the SETI project:In his [Richard Carrigan, a particle physicist at the US Fermi National Accelerator Laboratory in Illinois] report, entitled "Do potential Seti signals need to be decontaminated?", he suggests the Seti scientists may be too blase about finding a signal. "In science fiction, all the aliens are bad, but in the world of science, they are all good and simply want to get in touch." His main concern is that, intentionally or otherwise, an extra-terrestrial signal picked up by the Seti team could cause widespread damage to computers if released on to the internet without being checked.
Here's his website.
Although you have to admit, it could make a cool movie
(Via Schneier on Security.)