Have you finally configured yourself a shell you like? - Great!
Do you have a backup of the configurations? How about version history? And easy setup? - Why not?
Welcome [dotfiles]((http://dotfiles.github.com/): extract your shell configurations from the root of your home folder, and put them into a version control system. If you have not yet done it, do it now.
I highly recommend you to start by picking an existing set of dotfiles and fork it. This way you'll most probably get the easy setup, and a community support behind you. I've forked mine from Thoughtbot, because it has a very easy setup (and update), strong community, zsh-support and a stunning set of ready-made configurations.