One problem here is that I think the error message is for all Wikimedia projects. Scattered puzzle pieces of a globe is fine for Wikipedia.
Perhaps Wikibooks could have pages being torn out of a book.
Wikisource could have an iceberg melting into the sea.
Wikiversity could have the pillars of the academy tumbling down and the world falling down from suspension.
For Wikispecies, the DNA coils unfolded.
Wiktionary? The word Wiktionary with the label "a currently-offline wiki-based Open Content dictionary"
Commons could have the arrows pointing all over the place.
As for Wikinews? Well, duh, that should tell you that the site is offline as a breaking news headline.
Hmm, grey family logo:
http://commons.wikimedia.org/wiki/File:Wikimedia_logo_family.png
+ unhappy sunflower:
http://commons.wikimedia.org/wiki/File:MediaWiki_mascot_3.png
or Wikimedia logo with screwdriver and wrench:
http://commons.wikimedia.org/wiki/File:Wikimedia-cotw-notext.png
+ the rest of logos on the ground
Przykuta