There is, of course, a correct solution to this line length problem. The ideal maximum line length is dependent on how much horizontal space you've got, so the code should be automatically wrapped to your window size. That's how all other text displaying systems work, from html to word processors. It's just code that's the exception*.
This would require good automatic wrapping, which is a bit more difficult for code than for English, but automatic reformatting utilities already exist. It would also require tool support, so everyone would need to use editors like emacs or something else that's programmable. Just your favorite notepad-on-steroids variant won't suffice anymore.
Of course, it's only 2009 and this is all very much py-in-the-sky. (Though who knows what Python 6000 will bring...)
The only backward compatible way I can think of to implement this is to tell your emacs or other programmable editor to automatically display files according to your window width, and wrap them to 80/whatever cpl in the on disk representation when you save. And add some magic so it only changes those parts of the file in the on disk representation that you actually edited, deal smartly with line numbering, etc, etc.