I use Cell Writer on my ThinkPad X61t, and it works well enough, and is fast enough that I don't feel obliged to switch the display around to laptop mode if I'm in convertible-slate mode.
It's just that emacs was built around a keyboard and keyboard modifier keys.
I'd love to see a version of it re-worked around pen-computing --- there are a lot of neat ideas for that which aren't yet fully developed:
- codea ---
http://twolivesleft.com/Codea/ there are some nifty touch-interface-gestures for inputting parameters
- pie menus --- these need some more work, though I found the implementation in NovaMind really interesting
- gestures --- every time I get used to a set, I change machines or OSs --- they really should be built into a menu system though (to facilitate learning them) --- "Punch" in Altsys Virtuoso on my NeXT Cube was a quick, easy, fluid gesture which I found quite natural on my Wacom ArtZ
I've been meaning to look into Code Writer:
http://www.actiprosoftware.com/products/apps/codewriter --- wish there was a Metro (or native Mac OS X) version of LyX though:
http://www.lyx.org/
There are also some interesting alternative input systems --- Dasher is kind of cool, and I've always wished that the Lightning Link TabletPC on-screen keyboard had become more popular.
William