>> I want to use a small netbook exclusively for Org-mode. >> That's why I think I do not need X. > > You may not need it, but a lightweight window manager like WindowMaker > fvwm or maybe a tiling WM like awesome may be worth a second look. Have > a look here:
If the netbook will only be used for org-mode, and so perhaps only running Emacs, a WM might not even be necessary. If only one Emacs frame is used, it could probably be run on bare X.