At AppLand we're currently working on ways in which we can visualize how changes to the code affect program design and execution. But it turns out you don't need any fancy visuals to be able to tell something useful.
(BTW, see the whole code gallery!)
If you're not familiar with AppLand, at the very basic level, it allows you to record program execution traces. These traces can then be processed to surface interdependencies between code artifacts (such as classes, objects