Some physicists have posited a possible new hazard at the Large Hadron Collider at the CERN lab in Switzerland which may result from Bose Einstein Condensates, a super cold matter by-product of the LHC. The circuit of the particle accelerator is encased in a sea of superfluid helium (a known Bose Einstein Condensate) and strong magnetic fields a combination which can cause a huge explosion known as a Bose Einstein Supernova. But our friends at CERN say nothing to worry about.
Apparently the LHC is also harnessing the power of 100,000 computers through the use of the internet grid.
Disclaimer: I am not a particle physicist (and neither are you) 😀
Update: 01/23/09 Collider could create black holes that could last up to one minute.