Delete All EMails Simplifies Communications

In ComputerWorld:   In a review of the new Blackberry phone the idea of a  'delete all' email button is mentioned.  I remember that capability when I used a Backberry phone.  I now use an iPhone. You could quickly wipe clean the phone of new emails. They would remain archived in your laptop.  A simple idea like this would make it much easier  to have a 'working' list of important messages.  Nice idea, would like to see that on other OS's.   Lets see more simplifying eMail ideas.