Tatsuo Horiuchi

If my eyes were a 90's cathode ray tube screen, I have no doubt that the gridlines of an Excel spreadsheet would be permanently phosphor-burned onto my eyelids. Scientists, like actuaries, accountants, and Excel usability testers, stare at these thin, intersecting lines the same significant fraction of their lives. 

Unfortunate as this may be, this software has the latent capability to serve as a canvas for some creative souls, and Tatsuo Horiuchi from the Nagano Prefecture in Japan is just one of those people. Just look at this madness:

73-year old Horiuchi gained recognition through winning an Excel Autoshape Art contest in 2006, which is at the top tier of the "Obscure Competitions" list alongside the cheese rolling competition of Gloucestershire or the US Air Guitar championships

RocketNews24 has an archive of some of Horiuchi's work, proving that a wide variety of tools can be used for a creative digital artist, and that MAYBE you don't really need Photoshop or Illustrator for work.