LaTeX Beamer Tips

To include videos, do  
\usepackage{multimedia}
\movie[externalviewer]{\includegraphics{poster.jpg}}{film.mp4}

Without externalviewer, the PDF viewer attempts to play the video within itself (this usually does not work).

To cover/uncover parts of slide, do

\uncover<1-4>{Show this throughout.}
\uncover<2-4>{Show this after the first transition.}
\only<3-4>{Show this after the second transition.}
\only<4>{Show this after the third transition.}
Roughly, \uncover puts the text on the slide before the transition but hides it. \only doesn't put the text on the slide until the specified transition. You can replace the text with image (\includegraphics), environment, etc.

To have text on the left and an explanatory image on the right, (within the frame) do
\begin{columns}
    \begin{column}{0.5\textwidth}
        \begin{itemize}
            \item Blah
            \item Blah Blah
        \end{itemize}
    \end{column}
    \begin{column}{0.5\textwidth}
        \centering \includegraphics{Blah.jpg}
    \end{column}
\end{columns}

To display slide numbers in the footer, (in the preamble) do
\useoutertheme{infolines}
\setbeamertemplate{headline}{}
\setbeamertemplate{footline}{\insertframenumber/\inserttotalframenumber}
Move \insert... to headline to display in the header.