The 34 mm Audemars Piguet Royal Oak 50th Anniversary, reference number 77450st is the smallest Royal Oak that you can get with an Automatic movement. The 33mm models all come with Quartz movement.
The limited edition Breitling for Bentley Barnato Racing Chronograph, reference number R25366 is a big timepiece and hefty because large case that is made of 18K rose gold.