Russians tell aliens to suck on a fat one
хуй to you too, mate
Doubtless inspired by the UK's huge farmer's arse , Russian wags recently decided to send a message of their own to visiting aliens, and have succeeded in getting their greeting onto Yahoo! Maps :
For those of you not up to speed on Russian sexual slang, хуй translates as "cock". And what a collossal cock it is too, as these snaps  of the work in progress attest.
Sadly, the giant cock has not yet popped up  on Google Earth. We expect the powers that be will move quickly to update their servers in the interests of intergalactic relations. ®
Thanks to Mike Richards for the heads-up.