Great, another great demonstration of the fundamental principles of digital computing - representation and interpretation of data. It's been my experience teaching CS courses that many students, despite being taught bits and bytes and binary and ASCII and so forth, don't really "get it" until they see things like this.

This particular one only looks like a giraffe when it's interpreted as a 1bpp big-endian bitmap, but you could probably do the same with a colour (24bpp, in whatever order you wish) photo.

Here's another fun idea: write a short program that checks if a file is a prime number. Now you can get into the principles of CRCs, RS, and other error-correction codes...