GPL question

To any GPL experts reading this (e.g. novalis):

What is the minimum I need to do to make my code be covered by the GPL? Is it enough to upload it to a Sourceforge or Google Code project that has specified the GPL as its license? How about if I include the license file (COPYING)? Or do I have to put something in every single source file? Can I put a 1- or 2-line copyright statement, or do I need to include all 15 lines of boilerplate in each file? Can it go at the bottom, or does it have to go "near the top"?

Statues and paintings

I think jwz linked to this: strange statues around the world. But even better on the same site, a gallery of surreal art from three artists: Rob Gonsalves, Jacek Yerka, and Al Magnus.