Mark current column

[Peter Tury]

Hi,

I use GNU Emacs 21.3.1 on Win XP (I may switch to using CVS).
I've seen vvb-mode.

Is it possible somehow easily (=using at most a few elisp lines in .emacs?)
to highlight the current column (in all the (visible) lines of the current
buffer) by a (custom)key sequence?

This should work in a "toggle-manner": when I press the same keys on an
already highlighted column, it should be unhighlightied.

vvb-mode can highlight the column of a given number; I would like to add a
little more "intelligence": determine the number of the current column
(from current pos), then highlight it. -- I don't stick to vvb-mode...

Thanks in advance,
P