Not a theme, but a simple mechanism to reload the last theme you were using when you quit Emacs.

I keep the same .emacs.d on all my machines, but I like to use different themes from time to time without impacting my config.

remember-theme provides a very simple method of doing this. Once installed, it will autoload at startup, check ~/.emacs-theme file it uses to remember your last theme, and then load it (after disabling any preloaded themes). When Emacs is quit, the last theme loaded will be saved, ready to be loaded up next time.

To install it, make sure you have the marmalade-repo available to the emacs package manager and then do M-x package-list-packages and find remember-theme in the list. (press i and x to begin installing.)

You can find the code on github : https://github.com/jasonm23/emacs-remember-theme