[cbymnull] Music progress slider

Most graphical music programs denote the progress of playing through a song with a horizontal slider.  You are limited in precision by the width of your screen.  Consider a "slider" that is like a paragraph of text: slides off one end and continues down on the next line.  The slider is decorated with the waveform and/or spectrum.  The point is to be able to get millisecond or centisecond precision when clicking on a point in the song.

A slight variation has columns of spectrum, with the columns arranged left to right.  The columns are at a very slight angle, so that the time point of the song, when projected to the top of the screen proceeds like an old-school horizontal slider.  The shading of the slider changes to denote which part of the song has already been played, so the shading creeps from left to right.