It's funny. I have been coding in one language or another since the early 80s, and it was only this year that I encountered Yet Another Way to write a flip-flop.

  my $ff = 0;
  while( 1 ) {
    print $ff ? 'hee ' : 'haw ', "\n";
    $ff = 1 - $ff;
  }
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For some perverse reason this really appeals to me, although I refrain from using it in production code. It has a certain mathematical elegance.