Our ALOHA framework supports windows that can float or "dock" into a container window. It is a free framework. You can check it out at http://www.seneca5.com/aloha.html.
Each of the VI's run as a separate Agent. The framework can doc them into a parent window by using subpanels. A VI can be inserted/removed from a sub-panel any time you want, even if it is running. ALOHA manages all that for you. Or you can dive down into our code to see how it was done.
