http://www.google.cn/logos/earthday09.gif

Nice one!, i saw it on Google New Zealand

And there are AdWords ads too when clicking the doodle, pointing to Google Earth 5.0 download ads.

The search string is
http://www.google.com/search?q=earth+day&ct=earthday09&oi=ddle&cts=1240383333171&cts=1240385511116

I don't know what the cts parameters are, modified in a sense of good paranoid :)

Somebody just pointed out to me the Tri-Force at the bottom of the pic :P
(about 1/4 of the way accross)

Triforce @ Google. End of world imminent http://www.reddit.com/r/pics/comments/8ekdc/triforce_google_end_of_world_imminent/

http://img300.imageshack.us/img300/307/triforce.jpg

EPIC! I love Zelda so so very much!

As the saying goes, "newfags can't treeforce"
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http://i44.tinypic.com/op1guq.png

whats a triforce

The Triforce is a mystical object in many Zelda games, consisting of three parts which one has to collect in order to rebuilt it and get your wish :D