Zed stands for "Zope Editor" and consists of a server side application (ZedRoot) written in python and shipped as a Zope Product and a client side editor (Zed) written in C++ and Qt.
ZedRoot basically takes advantage of the Zope builtin xml-rpc server to "preformat" various zope objects' data, properties and methods to be easily edited via any xml-rpc client. I'm working on a C++ / Qt client, but anybody could write a client in any language to interface to the ZedRoot. Zed has only been tested on Linux (RedHat 9), but may work with other Qt supported platforms (including windows).
Zed uses QuteXR as its xml-rpc library and QScintilla as it's main editing widget. Since it uses QuteXR, it requires Qt 3.1 and above, it works with RedHat 9 out of the box.
To start using Zed with zope, you must instantiate a ZedRoot object anywhere in your Zope tree. Once this is done, you may add the Zope site to the Zed site manager and off you go.
By default, ZedRoot ships with support for Folders, DTML Methods, DTML Documents, Z SQL Methods and Python Scripts. Adding support for other types should be easy, see $ZOPEDIR/lib/python/Products/ZedRoot/types.