Description of Problem: 
When I receive a letter with lot of people in the CC and/or TO, the message 
header become big, and it occupied too big place in the screen.  
I often have this problem, and there is no way to hide the message headers. 
 
Steps to reproduce the problem: 
In the message plane, display a message with lot of CC or TO in it's header. 
Even in 1024x768 it could become too big, not leave place for message body. 
 
Actual Results: 
Need to scoll down, to see the body, but it's not convinient. 
 
Expected Results: 
Put a "Hide Headers" ot "Short Headers" to Message Display menu. 
Show headers could display the TO, and SUBJECT in one line. 
 
Additional Information: 
I think, it's a really required feature and easy to implement.