This is great: The artist Danielle Aubert uses Microsoft Excel as a way to create pictures. As she writes on her site:

Microsoft Excel is a program designed to track and compute information, but here I am using Excel as a drawing tool. These drawings are a part of a series of sixty drawings that I executed (more or less) every day for fifty-eight days. Each drawing is in a new 'worksheet,' which is automatically set up as a grid. These drawings were made by changing cell preferences for background color, fill pattern, and border styles and from time to time inserting 'comment' boxes and letters or words.

It reminds me alternatively of byzantine mosaic, early computer-graphic pixel-art, and paint-by-numbers. The latter is kind of the most intriguing concept of all: It'd be fun to see her release the drawings as a set of cells, each with a number in it corresponding to a color, like a classic paint-by-numbers. Then you just use the "fill in cell" command to plop the right color in each cell, and there's your picture!

I've excerpted one of her more "realistic" pictures above, but she uses the technique to produce all manner of styles. Check her archive online here -- I can't link to individual creations, but a few of my favorites include March 16 (which looks like a sort of punchcard surrealism done in the Collision-Detection color scheme) and April 3, which looks like a concrete poem created on an Atari 2600.