In 2009 the “Tux” penguin logo was temporarily replaced for kernel 2.6.29 with “Tuz”, to highlight the plight of the Tasmanian Devil that was close to extinction.
Tuz (Tasmanian Devil) kernel 2.6.29 logo
http://linuxforums.org.uk/MGalleryItem.php?id=1485
Now there’s a proposal from Darrick Wong of IBM to (temporarily) replace the well known “Tux” logo again for kernel 3.1 with this logo.
Proposed kernel 3.1 logo
http://linuxforums.org.uk/MGalleryItem.php?id=1486
An obvious p*ss take of the Windows 3.1 logo.
http://linuxforums.org.uk/MGalleryItem.php?id=1488
Can’t see it actually being “officially” sanctioned (that “Flying Windows” logo is bound to be copyrighted), but I thought it may amuse you anyway. 
Sources:
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