With the latest release of our Wireframe software, we introduced sticky arrows.
Simply put, sticky arrows stick to any widget that it touches. The bezier lines, straight lines and other curves all have this abilty to stick and follow the widgets wherever you drag them.
With this feature you can build workable Flowcharts and FlowDiagrams. It is really so simple to use but provides a whole new dimension and flexibility.
Full blown flowchart functionality is still in the pipeline but this should atleast get some basic flowcharts accomplished.
We are using our own software extensively for documentation and internal presentation purpose (yep dog fooding)
The sticky arrows not only snaps to the edges but can be dragged deep inside any object dimensions so you can really use it for quick documentation and demonstration.
Just check this silly but live document. Try to drag any object, everything stays connected