Custom Action for Adding a Menu to Site Actions in SharePoint 2010

<Elements xmlns="http://schemas.microsoft.com/sharepoint/">
  <CustomAction
   Location ="Microsoft.SharePoint.StandardMenu"
   GroupId ="SiteActions"
   Title ="ShalvinAction">
    <UrlAction Url="javascript:alert('Hello from Shalvin {SiteUrl}');" />
  </CustomAction>