...
1.0.9 - The flames on the envelope may give the opposite viewpoint of 1.0.8 - instead of being too permissive, here's a fearful vision of the future where your mail will catch on fire or be destroyed. Again, this lacks the feeling of discrimination.
I think that most people will draw the conclusion that black mail equal bad mail. – ChristianHansen
1.0.15 - the lock on the envelope. Well this is closer than 1.08/1.09 in my opinion but still doesn't give the right feel - it would be great for SECURING or ENCRYPTING, but maybe not right for spam.
Might I suggest (and I do so humbly for my artistic skill is nil) to the artists that if one wants to illustrate the action upon the mail itself that the motif of filtering or selectivity is paramount.
Who are you? It would be nice if you would sign your comments! – ChristianHansen
Some interesting background
...