Outstanding! Every time I see one of those "No Weapons or Firearms" signs posted somewhere, it makes me think how they might as well put up a sign reading "Robbers and Murderers Welcome Here."
Our concealed carry law allows businesses to post that no firearms are allowed on the premise. I always ignore the signs because the penalty is only a simple trespassing ticket if they find out I'm carrying, and I refused to leave.
Unfortunately, I don't carry on school property or in a post office. The federal gun-free school zone law hasn't been over-ridden by the state here, so I have to pull over within 1,000 feet of the school property, unload my weapon, and place it in the trunk. Even off-duty law-enforcement officers have to do that. This is rather stupid, as it increases the possibility of an accidental discharge when you have to load or unload a firearm.