With respect, this is a crucial point if one desires to be taken seriously by gun owners when talking about guns, because confusing it reveals a lack of basic knowledge of the subject.

There is a magical center of action, greatly to be desired, where one neither runs over others nor lies down to be overrun.

SPF is essentially a self-maintained whitelist.

Blacklists are public and searchable. Something to check after dealing with an infected machine, for example.

The "hack" here, is merely getting the information out...historically not easy.

The way he tells it, no one ever got in trouble for subpar products. But if production numbers were down, someone was going to the gulag.

Apparently, consumers were aware of this and would try to obtain goods that were produced near the start of each month.

On the other hand, if the neighbors are burning wet wood, pine or otherwise Doing It Wrong maybe they would appreciate a friendly heads up.

Ought to be maintenance free and a nice way for the big trucking lines to differentiate their public face - similar to those aero ground effects that are showing up on trailers.