Spending a large portion of my time on university campus, I get many glances. Some from amateurs who are interested themselves in 'big cameras', or wants to report back to a friend who owns one. Innumerable folks walking about with bright 'CANON 5D mkII' straps around their necks here. I've also been assumed to be shooting for some media purposes for the university (which I have done briefly), and have gotten myself into events without credentials in the past walking in with confidence and a D3+70-200, folks here seem to be very aware of what big cameras look like. With eyes shifting back and forth so quickly and in such high volume of students walking around, it's pretty challenging to shoot unnoticed. I've been most successful so far with tilt-displays and waist-level finders; it appears that the motion of raising a camera to the eye calls much attention. Alternatively, standing around and pretending to fumble about with my settings like a novice seems to diffuse indirect tension in the air a small bit, like turning away from a wild animal as it senses your approach.
With medium format, I've been a bit of a spectacle, getting comments here and there, mostly from older gentlemen about how they shot similar cameras and how surprising it is to see someone my age (21) shooting MF film. Once at the Getty museum in L.A., I was approached by three gentlemen from different parties, all excited about seeing a RB67 in the wild. Perhaps I've met one of you from this forum?