This is a simple script that allows you to choose an area that will be recorded into a 10s animated gif.
screencapture [dest-file]
You need X11 + xrectsel + byzanz-record. Get it from the cool guys.
#!/bin/bash
echo "select screen region to capture"
rect=$(xrectsel)
dimensions=$(echo $rect | cut -d + -f 1)
width=$(echo $dimensions | cut -d x -f 1)
height=$(echo $dimensions | cut -d x -f 2)
x=$(echo $rect | cut -d + -f 2)
y=$(echo $rect | cut -d + -f 3)
echo "starting in 2"
sleep 2
echo "recording"
byzanz-record -w $width -h $height -x $x -y $y $@
echo "done."
echo "repeat screen capture via"
echo "> sleep 2 && echo \"recording\" && byzanz-record -w $width -h $height -x $x -y $y $@"