Reading all of these GUI wish-list posts, I just finished adding colored signal patch cords. It seemed like the easiest. I should probably test it a little more before I release a patch (probably later tonight). It was pretty simple, just check whether the connecting outlet is a signal with obj_sigoutletindex() in canvas_drawlines() and canvas_doconnect().
I was wondering if anyone had an opinion as to what the signal patch cords should look like. I think Max/MSP does yellow with ~'s. My personal preference is a slightly thicker solid blue line. Tk does have a -dash parameter for canvas objects, but I think it looks pretty awful.
Joe