HowTo: Write invoices in LaTeX

I generate all my invoices with LaTeX. It's very comfortable thanks to the latex-invoice package which handles all the calculations and most of the layout. Below is an example document ( this is what it will look like):

\documentclass{letter}
\usepackage{invoice}
\address{My Name \\ My Street \\ My Zip\\ my@mail.com \\ etc}
\signature{Fnord Prefake}
\date{23. May 2009}

\begin{document}
  \begin{letter}{Customer name \\ Customer street \\ Customer ZIP}
    \opening{Invoice no. 1}
    My greeting
    \begin{invoice}{Euro}{0}
      \ProjectTitle{Example Project}%
      \Fee{Development} {1000.00} {1}
    \end{invoice}
    \closing{My closing}
  \end{letter}
\end{document}

Running debian? Lucky you! Installing latex-invoice is super easy:

apt-get install texlive-latex-extra