Custom webkit based application

I need an application similar to this: [login to view URL] What I am after is an interface that combines several different web sites into 1 single window, with tabs, a sidebar or two, etc. Each element would be a site, defined by my own URLs. It must support javascript, desktop notifications, etc. Basically i want all sites to function inside one window app. Please see crude mockup attached. When tabs are clicked, it will switch the biggest display area. The two sidebars shows should be static, and always display. This application should allow customization for what sites are rendered in which block. Block dimensions should also be customizable. Finally, this should support single sign-on through LDAP.