A question of van den Dries and a theorem of Lipshitz and Robinson: Not   everything is standard
  We use a new construction of an o-minimal structure, due to Lipshitz and Robinson, to answer a question of van den Dries regarding the relationship between arbitrary o-minimal expansions of real closed fields and structures over the real numbers. We write a first order sentence which is true in the Lipshitz-Robinson structure but fails in any possible interpretation over the field of real numbers. 
Ehud Hrushovski, Ya'acov Peterzil