(I'm almost hesitant to begin a Virtual Reality weblet, but it's GOING to be a part of scientific visualization if it isn't already. Here are some likely-looking links):
Some Applications of Virtual Reality
from U. Minnesota Geometry Center
Virtual Reality Is...
from Sandia Labs
Cognitive Factors Associated with Immersion in Virtual Environments
(Psotka and Davison)
Center for Coastal Physical Oceanography VR research
at ODU
Open Virtual Reality Testbed
from NIST
Entertainment: Virtual Reality
from YAHOO