Updateable Web Sites

I'm looking for some code that will enable me to create a updateable web
site. So when I design a the front end all I need to do is drop in some
server variables on the html pages and the asp code does the rest via a
database.

The code would be portable therefore small changes will allow me to apply to
many sites, ideally it should also contain a text editor.Is this feasible ?
I've looked at cms, but this doesn't seem to give enough flexibility or am I
missing something ? and finally asp.net has some sort of portal system
(matrix), how does this fit in ?

For the moment I think the best way forward is this code (or framework) that
will enable the client to update, until a better sollution.