A dime a dozen means something is common place and plentiful.         

Lawyers in the United States are a dime a dozen.    

Sun Yang: Why don’t you buy a Hyundai. They are reliable cars.             

           Sang mi: Hyundai’s are a dime a dozen in Korea. I want something different and

                           unusual. I want a Porche.

I’m all ears means one is listening. 

 Father: Son, I have something important to tell you. 

  Son: Go ahead dad, I’m all ears.