This is another shot that I took with my 70-200 and 2x converter combo last year when I was out in Yellowstone.  I was admittedly way too close, but I was using natural blinds and I don't think the critters were very worried about me.  For folks who have seen me post this in the past, I apologize for the re-post.  It is just, IMO, a good example of what you can do with the 200 with 2x converter.
 