The difficulty is finding the mouse position so that the dialog can be displayed at the mouse...
Imagine having a small compact form that you can dispay right at the mouse coordinates that can act like a pop menu but can have text boxes, check boxes, radio buttons, tree controls, dropdown boxes etc.
I have a routine for AutoCAD Architecture: a toolbar with buttons for each object type, door, wall, etc. When the user picks the button a form is displayed at the button (like a pop menu) but has a list box with all the available styles. Double click the style you want, the form goes away and that command is fired with that style active. Saves a ton of drafting time.
Just sayin.
