Hi,

This is very useful to show processing image when some action going on.
Some time we forget how to show this so I post in my Blog to quick remember.

           

<apex:form>

   <apex:commandButton  status="statusProcess" action="{!actionA}" /> 

    <apex:outputPanel id="statusProcessId">

       <apex:actionStatus id="statusProcess">
               <apex:facet name="start">
                   <apex:outputPanel > 
                      &nbsp; Requesting...<img src="/apexpages/devmode/img/saveStatus.gif" />
                   </apex:outputPanel>  
               </apex:facet>
            </apex:actionStatus>
       </apex:outputPanel>
</apex:form>

Thanks

Ashlekh Gera