I'll be testing this with different color schemes, but yeah, works! Addition: for eink readers, would underline or italics work in place of color gradient?
[1] http://en.wikipedia.org/wiki/Line_printer#Paper_.28forms.29_... "The paper was usually perforated to tear into cut sheets if desired and was commonly printed with alternating white and light-green areas, allowing the reader to easily follow a line of text across the page. This was the iconic 'green bar' form that dominated the early computer age. " (emphasis mine)