Apparently if you set this to a non-nil value and if you're at the end of a line, C-n and C-p will track up or down to the end of the line you just moved to.
(setq track-eol t) ?
I've enabled it in the past and I can't say I found it tremendously useful and wondering if anyone has ever seen some good use for it. It's mentioned in the manual. Drop me a line if you ever think of a good use for it. I have a nebulous thought it might be useful for fixed width data files?
*shrug*
Copy it to the scratch buffer, eval it and open a few text files and see whether you like it all.