Enable or Disable Claims Based Authentication in Share point 2010 using power shell

Scenario:
You may require to change an existing web application to use claims. But there is no option to change it from Central Administration. Central Administration provide option only when creating site.

If so, then how to change existing web application to use claims?
SharePoint 2010 Management shell comes to rescue. You can use shell commands to enable or disable claims on web application.

Shell Command:

$existingwebapp = Get-SPWebApplication "http://siteurl"
$existingwebapp.UseClaimsAuthentication = $true
$existingwebapp.Update()