I want this. A thing that let's you visualize how the routines in your program are interconnected and how complex your routines are.
* Lines pointing from the current routine to other routines it uses.
* Lines pointing into the current routine from other routines which use it.
* Lines connecting any global (which includes lexicals scoped outside a routine) your touine uses to all other uses of the global to show just how they interconnect (and toss encapsulation out the window).
* A visualization, either with color or length, of the length of each routine.
* A visualization of how deeply nested a routine gets.
Those last two, in particular, are really good, cheap indications of complexity.