Night minima under Part 135 are 1 mile visibility, and sufficient surface lights to safely control the aircraft. I suspect many pilots forget about the latter requirement, because with 1 mile visibility you won't have many surface lights in sight outside an urban area. Flying at night with 1 mile vis is really pushing the envelope, IMO. Our company minimum is 1000/3, and I will seldom fly VFR with that weather, only in the immediate vicinity of the airport. Cross-country, at night, with 1000/3 is simply too dangerous for me to even consider. Lots of people do it, though, and even with 1 mile and an unknown ceiling. Whether it's because of economic and job pressure, or because of the hero syndrome, it's becoming increasingly fatal. We have entirely too many EMS pilots trying to be heroes, but killing the patient isn't heroic in any sense, nor is killing yourself and/or the medical crew. It's simply stupid.