Document Class for Reference Cards

As a start. Class version tested and seems to produce the same output, with a few changes to \maketitle. Edits welcome.

\documentclass[10pt]{article}
\usepackage{fixltx2e}
\usepackage[orthodox,l2tabu,abort]{nag}

% Page layout
\usepackage[landscape,margin=0.5in]{geometry}
\usepackage{multicol}

% Title area
\usepackage{titling} % Allows for use of date, author, etc. after \maketitle
% Ref: http://tex.stackexchange.com/questions/3988/titlesec-versus-titling-mangling-thetitle
\let\oldtitle\title
\renewcommand{\title}[1]{\oldtitle{#1}\newcommand{\mythetitle}{#1}}
\renewcommand{\maketitle}{%
{\begin{center}\Large \mythetitle\end{center}}
}

% Document divisions
\usepackage{titlesec}
\setcounter{secnumdepth}{0}
\titlespacing{\section}{0pt}{0pt}{0pt}
\titlespacing{\subsection}{0pt}{0pt}{0pt}
\usepackage{nopageno} % To keep \section from resetting page style

\setlength{\parindent}{0pt} % disabling indentation by default

% Lists
\usepackage{enumitem} % for consistent formatting of lists
\newlist{ttdesc}{description}{1}
\setlist[ttdesc]{font=\ttfamily,noitemsep}
\usepackage{calc} % for \widthof

% Code
\usepackage{listings}
\lstset{language=[LaTeX]TeX,%
  basicstyle=\itshape,%
  keywordstyle=\normalfont\ttfamily,%
  morekeywords={part,chapter,subsection,subsubsection,paragraph,subparagraph}%
  }

\usepackage{lipsum}

\title{\LaTeXe Cheat Sheet}
\author{Winston Chang}
\date{2012}

\begin{document}
\begin{multicols}{3}
\maketitle

\section{Document classes}

\begin{ttdesc}[labelwidth=\widthof{\texttt{report}}]
\item[book] Default is two-sided.
\item[report] No \texttt{part} divisions.
\end{ttdesc}

\subsection{Common \texttt{documentclass} options}

\begin{ttdesc}[labelwidth=\widthof{\ttfamily{letterpaper/a4paper}}]
\item[10pt/11pt/12pt] Font size.
\item[letterpaper/a4paper] Paper size.
\item[draft] Double-space lines.
\end{ttdesc}

\section{Document structure}

\vspace{-\baselineskip}

\begin{multicols*}{2}
\lstinline|\part{title}| \\
\lstinline|\chapter{title}| \\
\lstinline|\section{title}| \\
\lstinline|\subsection{title}| \\
\lstinline|\subsubsection{title}| \\
\lstinline|\paragraph{title}| \\
\lstinline|\subparagraph{title}|
\end{multicols*}

\section{Text properties}

\subsection{Font face}

\begin{tabular}{lll}
Command & Declaration & Effect \\
\lstinline|\textrm{text}| & \lstinline|{\rmfamily text}| & \textrm{Roman family} \\
\lstinline|\textsf{text}| & \lstinline|{\sffamily text}| & \textsf{Sans serif family} \\
\end{tabular}

\section{Math mode}

\subsection{Math mode symbols}
\begin{multicols*}{4}
\( \leq \) \verb|\leq| \\
\( \times \) \verb|\times| \\
\( ^{\circ} \) \verb|^{\circ}| \\
\( \infty \) \verb|\infty| \\
\( \supset \) \verb|\supset| \\
\( \subset \) \verb|\subset| \\
\( \cup \) \verb|\cup| \\
\( \dot a \) \verb|\dot a| \\
\( \alpha \) \verb|\alpha| \\
\( \epsilon \) \verb|\epsilon| \\
\( \theta \) \verb|\theta| \\
\( \lambda \) \verb|\lambda| \\
\( \pi \) \verb|\pi| \\
\( \upsilon \) \verb|\upsilon|
\end{multicols*}

\section{Filler material}

\lipsum

\noindent Copyright \textcopyright{} \thedate{} \theauthor{}

\end{multicols}
\end{document}