So, I download RocketDock, and it turns out to be pretty cool. Of course, I disagree with its claim to be the "greatest piece of software ever", but that's my problem.
So I'm populating the dock, and I drag Sauerbraten onto it. Being of the picky type, I completely dislike the idea of having the fugly icon of a batch file representing the greatest piece of software ever.
So I fire up Photoshop, whip up a dock icon, and sucker it onto Sauer's little spot, and voila! That's much better.

I decided to share this icon with the world, in hopes that someone will actually like it. It's in .PNG format, the default dock icon format, so live with it.