\documentclass{beamer}
\usetheme{simple}
\usepackage{lmodern}
\usepackage[scale=2]{ccicons}
% TODO: 
%   position adjustement
%   change colours
%       
% Watermark background (simple theme)
\setwatermark{\includegraphics[height=8cm]{img/Heckert_GNU_white.png}}
\title{A simple beamer theme}
\subtitle{}
\date{\today}
\author{Facundo Mu\~noz}
\institute{\url{http://github.com/famuvie}}
\begin{document}
\maketitle
\begin{frame}{simple}
  \framesubtitle{A beamer theme}
  \texttt{simple} is a minimalist Beamer theme that features
  \begin{columns}
    \column{.5\textwidth}
      \begin{itemize}
        \item a \alert{watermark} logo in the background
        \item slide \alert{numbers}
        \item \emph{emph}asized and \alert{alert}ed text
      \end{itemize}
    \column{.5\textwidth}
      \begin{block}{And of course...}
         blocks, columns, and all Beamer power
      \end{block}
  \end{columns}
  
\end{frame}
\setwatermark{\fontsize{125pt}{125pt}\selectfont{Simple}}
\begin{frame}[fragile]{watermark}
  \framesubtitle{not only for images}
  \begin{itemize}
    \item You can place \emph{any} \LaTeX{} \alert{contents} as a watermark
  \end{itemize}
  \begin{block}{In preamble}
    \begin{verbatim}
     \setwatermark{\includegraphics[height=8cm]{%
                   img/Heckert_GNU_white.png}}
    \end{verbatim}
  \end{block}
  \begin{block}{Just before this frame}
    \begin{verbatim}
     \setwatermark{\fontsize{125pt}{125pt}%
                   \selectfont{Simple}}
    \end{verbatim}
  \end{block}
\end{frame}
\setwatermark[hoffset=-3cm,voffset=-2cm]{\fontsize{125pt}{125pt}\selectfont{Simple}}
\begin{frame}{Options}
  \framesubtitle{Fine adjustement of the watermark position}
  
  \begin{itemize}
    \item \texttt{hoffset}
    \item \texttt{voffset}
  \end{itemize}
  
  They admit any \emph{positive} or \emph{negative} spacing \alert{unit}
  
  Note that some \alert{warnings} about \emph{badboxes} might be generated at compilation
\end{frame}
\begin{frame}{License}
  \begin{block}{Get the source of this theme and the demo presentation from}
  \begin{center}\url{http://github.com/famuvie/beamerthemesimple}\end{center}
  \end{block}
  
  The theme \emph{itself} is licensed under a
  \href{http://creativecommons.org/licenses/by-sa/4.0/}{Creative Commons
  Attribution-ShareAlike 4.0 International License}.
  \begin{center}\ccbysa\end{center}
\end{frame}
\end{document}