I'm wondering if there's a way to save window configurations across emacs sessions. I know desktop-save is fantastic for preserving buffers and whatnot and the emacs manual demonstrates storing a window configuration into a register but this doesn't persist across sessions.
Of course this doesn't seem like it would be too hard to implement myself...
EmacsWiki is a great resource: EmacsWiki: Session Management
Looks like Windows Mode, or more specifically revive.el, is what you want.
A lot has changed since 2008, and desktop-save-mode
now also restores windows accross sessions. Emacs 24.4 and higher.
winner-mode is also interesting (->EmacsWiki)
(winner-mode 1) ; add this line to .emacs
Now, you can go back to previous split pane config by Alt+x
winner-undo 【Ctrl+c ←】. There's also winner-redo 【Ctrl+c →】.