Please beware, however, false positives could occur and be attributed to an increase in room humidity (i.e shower steam & humidity), elevated dust levels (i.e pillow fight), or an abrupt increase in heat (i.e sauna)
People called such cigarettes Eye Gouges, or Death to the Fascists
Any otherwise mailable matter that reasonably could be considered a bill, invoice, or statement of account due, but is in fact a solicitation for an order, is nonmailable unless it conforms to 13.1.2 through 13.1.5 in Solicitations in Guise of Bills, Invoices, or Statements of Account (39 USC 3001(D)
Some would argue that changing the lighting detracts from the performance, and while Im not suggesting having a disco ball whirling around during the slow movement of a Mozart symphony, I was surprised at how my mindset and expectations changed simply in relation to how the stage looked