
The roller is one of the more visually interesting widgets, behaving much
like the volume control of an old transistor radio.

The default roller, which is controlled by an up/down drag, seems to be
the opposite of what it should be, in my opinion. I feel that dragging *up*
should increase its value. Reversing the minimum and maximum values only
serves to make it appear to turn in the opposite direction of the drag.

The roller is quite good in that it will continue to work as long as you
continue a single drag, regardless of whether the cursor leaves the widget.
