This picture was an illustration for a computer game in my Computer Science class.  I don't particularly like it, but it was kind of neat.  The horn is supposed to be glowing, but because I was really bad at computer coloring when I did this, it just looks weird.

I guess this picture might be the genesis of my thought that horses could be, given certain adaptations, very vicious creatures.  I didn't want my unicorn to be the staple nice, pure, etc, I wanted it to be mean, evil, and nothing you'd want to be nearby.