City64 at least fails to produce the same values on an x86 and big endian PPC (Debian squeeze on both):

  x86
  ========================
  641f1cd0505d1ff9 : I
  e394c6831e9d6e71 : do
  651c1a4b0b3f2d88 : not
  9fc671af2d051786 : know
  1fa385757f0016ec : about
  f2407bd9ce678f7f : making
  73bd225c6b6b8163 : awkward
  ea78562e35777eb1 : rhopalic
  3c854a925e6e4a9e : sentences
  84a04e9aa8dae9f5 : .
  
  PPC
  ========================
  641f1cd0505d1ff9 : I
  e394c6831e9d6e71 : do
  651c1a4b0b3f2d88 : not
  147d90cc620fc6b2 : know
  23af6044b2394703 : about
  4f80227202845190 : making
  4b8b4b3cd98a1de9 : awkward
  61b38def2ee9465f : rhopalic
  29016ee1c7c61e93 : sentences
  84a04e9aa8dae9f5 : .

For anyone that cares, the test program was…

  #include <stdio.h>
  #include <string.h>
  #include "city.h"

  const char *word[] = { "I", "do", "not", "know", "about",
                         "making", "awkward", "rhopalic", 
                         "sentences", ".", 0 };

  int main(int argc, char **argv)
  {
      for ( const char **p = word ; *p != 0; p++) {
        uint64 v = CityHash64( *p, strlen(*p));
        printf("%Lx : %s\n", v, *p);
      }
  }