Starting on October 1, 2009...Avis and Budget car rental companies are going smoke free.  They will impose a $250 'cleanup' fee if you decide to spark up on your trip.  The new rule is in response to the #1 request of it's customers...a Non-Smoking car.  I'm thinking they are also making the move to protect the cars interior...since smoke and ash really can cause some damages. 

No other rental companies have followed suit yet...but I'm thinking it will be only a matter of time.  I can just see it now...the gas stations near the rental centers will start to offer super Fabreeze or air-fresheners so renters that smoke can try and mask the smell.  I wonder how Avis and Budget will know you've been smoking?