my two cents

From dotfiles.org; original author unknown. I found this code here: http://www.shell-fu.org/lister.php?id=375

###   Handy Extract Program

extract () {
if [ -f $1 ] ; then
case $1 in
*.tar.bz2)   tar xvjf $1        ;;
*.tar.gz)    tar xvzf $1     ;;
*.bz2)       bunzip2 $1       ;;
*.rar)       unrar x $1     ;;
*.gz)        gunzip $1     ;;
*.tar)       tar xvf $1        ;;
*.tbz2)      tar xvjf $1      ;;
*.tgz)       tar xvzf $1       ;;
*.zip)       unzip $1     ;;
*.Z)         uncompress $1  ;;
*.7z)        7z x $1    ;;
*)           echo "'$1' cannot be extracted via >extract<" ;;
esac
else
echo "'$1' is not a valid file"
fi
}