How do I make a presentation that seems made on an overhead projector?

Question

I want to do a presentation simulating an overhead projector which some professors used when I was a math student.

I couldn't find an image to mimic the background produced by an overhead projector. Also I was trying to make the text a little blurry using this: Blur the text so it's not readable, but it would be better if the entire document (background and images) is a little blurry and yellowish. I'm using a different font to simulate handmade annotations (http://www.google.com/fonts/specimen/Permanent+Marker).

Being more specific:

• Background produced by an overhead projector.

• Blurry and yellowish document.

• Handmade annotations across the text.

Edit: Minimal example without text blur

\documentclass{article}
\usepackage[pages=all]{background}
\usepackage{fontspec}
\usepackage{color}
\newfontfamily\myfont[Scale=2.5]{PermanentMarker}
\usepackage{lipsum}

\backgroundsetup{
opacity=0.4,
angle=0,
contents={%
\includegraphics[width=\paperwidth,height=\paperheight]{background-image}
}%
}

\usepackage[overlay,absolute]{textpos}

\begin{document}
\lipsum[1-5]
\begin{textblock}{5}(6,6)
    {\myfont {\color{blue} Some annotations}}
\end{textblock}
\end{document}

Answer 1

According to @James comment I tried an imagemagick approach to answer my own question.

This is a small example (compiled with XeLaTeX), Google Permanent marker font is needed (http://www.google.com/fonts/specimen/Permanent+Marker)

\documentclass{article}
\usepackage{fontspec}
\usepackage{color}
\newfontfamily\myfont[Scale=2.5]{PermanentMarker}
\usepackage{polyglossia}
\setdefaultlanguage{english}
\usepackage{blindtext}

\usepackage[overlay,absolute]{textpos}

\begin{document}
\begin{textblock}{8}(4,6)
    {\myfont {\color{blue} Some annotations...}}
\end{textblock}
\blindmathpaper
\blindmathpaper
\begin{textblock}{8}(2,8)
    {\myfont {\color{blue} More annotations...}}
\end{textblock}
\end{document}

For the imagemagick part I used Color filter script from (http://www.fmwconcepts.com/imagemagick/colorfilter/index.php)

#!/bin/bash

if [ $# -ne 2 ] ; then
   echo -e "You  must specify two parameters: filename and corner option s (square) or r (round)."
   exit 1
fi

if [ ! -f $1 ]; then
    echo "File not found!"
    exit 1
fi

if [ "$2" != "s" ] && [ "$2" != "r" ] ; then
   echo "Error in corner option, must be s or r"
   exit 1
fi

output="op_$1"
convert -density 200 $1 -quality 00 -background white -alpha remove page-%d.png

for img in `ls page-*.png`
do
if [ $2 == "s" ]
then
convert $img\
        \( -size 300x200 xc:none -draw "fill black polygon 0,0 0,200 200,0" \
       -write mpr:triangle  +delete \) \
        \( mpr:triangle             \) -gravity northwest -composite \
        \( mpr:triangle -flip       \) -gravity southwest -composite \
        \( mpr:triangle -flop       \) -gravity northeast -composite \
        \( mpr:triangle -rotate 180 \) -gravity southeast -composite \
        $img
fi
if [ $2 == "r" ]
then
convert $img \
        \( +clone -alpha extract \
           -draw 'fill black polygon 0,0 0,300 300,0 fill white circle 300,300 300,0' \
        \( +clone -flip \) -compose Multiply -composite \
        \( +clone -flop \) -compose Multiply -composite \
        \) -alpha off -compose CopyOpacity -composite -compose \
        over -background black -flatten \
        $img
fi
./colorfilter -m 1 -c warming81 -d 45 $img $img
convert $img -blur 3x1 $img
done

convert page*.png -gravity center $output
rm -f page*.png

Please feel free to correct or improve my answer.

Edit: Screenshot added.