Homebrew PCBs

I saw a site a while back where a guy was using a PCB sensitizing 
spray in a can.  It was from Europe...I can't remember what it was 
called...GPC or something.  You just sprayed it onto a board, 
exposed, developed and etched.  I looked and looked and even emailed 
a bunch of companies to find it, but never did.  I am told it is 
fairly hard to use, as it is said to be tricky to get the right 
uniform thickness of the stuff on boards.
  I'd still like to try it though.  Does anyone know what some of 
these products are called and/or where to find them in the US?

-Josh