Yes, we here at HGP have heard that a sentence shouldn't end in a preposition, and we even know some folks who are passionate about it, which could explain why nobody likes to hangout with Mrs. Vula Bimbaum.  Here's the thing:  It's not a real rule.  Never has been.  Sure, it's a rule in Latin, but not even priests speak Latin anymore.  It seems that at one time some English teacher who also taught Latin (not to name anybody in particular) thought because it was a rule in Latin then it should also be a rule in English.  And then it just sort of... transmogrified.  Mostly now, people who care about such things say that sentences ending in prepositions are more informal, and therefore shouldn't be used in formal writing.  Good for them!  But here's the thing:  Formal or informal, if you can't end a sentence in a preposition, how are you going to be able to tell somebody to bugger off?