[Zope] maintaining a variable

[Josh On]

Hello

I want a single interger variable that can be accessed and updated from dtml
files in various folders.

I want to be able to do things like x=x+1
and ask what x is.

what is the best way to do this in zope?

Where might I read a tutorial on it?

Please note I have classes and catalogs and sql methods working (to a
certain degree!) but I really am having problems getting a simple solution
to this problem.

Presently I have set the variable as a property of a folder.  I want to
update it from a method inside a dtml file inside that folder, but have not
been able to work out its address.

I can read the variable, but I think that that is thanks to aquistion?

Thanks for your time

josh oN

(sorry for cross postings on this topic, I won't post to zope dev anymore!)