1-up your average quine
GolfScript, 12 bytes

{`'.~'+:n}.~


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Explanation

This combines ideas from the standard GolfScript quine:

{'.~'}.~


And my recently discovered quine:

":n`":n`


The main idea is again to use n which is printed implicitly at the end of the program in order to get the additional copy of the quine. Since assigning the variable doesn't change anything when it's done again in subsequent copies, this will only add one copy. Here's a breakdown of the code:

{        # Standard quine framework. This pushes the block, duplicates it and runs the
         # second copy, such that it can process the first copy to create a quine.
  `      # Convert the block to its string representation.
  '.~'+  # Append the string '.~' to make a complete quine. This is simply left on the
         # stack to be printed at the end.
  :n     # Store the string in n such that one more copy is printed at the end.
}.~