In a web based LOB (Line of Business) application,I want to keep top level menu options always available for user. I want the data for a given business operation (such as customer information maintenance) visible when the user opens related information (orders, for example). Given the limited real-estate, what options have you seen in practice other than MDI (Multi Document Interface) to effectively accomplish this? I know other options exist, for instance by opening a new web page but this option can't be used, because the application is not aware of the new opened page and can't close it automatically. Splitter with docking, is another option, but business users many not be very familiar with it and may require some initial getting used to (I guess so at least). If you could provide an example of what you consider a relevant solution, I would be thankful.
A tabbed UI might be used to accomplish much of what MDI did. A global menu could exist above the tabbed widget, and each tab/page could have a tab specific menu.
The behavior of tabbed UIs is well understood these days and fit in the single webpage paradigm.
Of course tabs have the constraint of not showing more than one tab/page at a time, so that may be a deal breaker for you.