Realtime Web chat for Zope. Available either as Python product or ZClasses product. Employs some of the basic things many products need to do in Zope, so I call it an example product.
The 0.3.0+ version is almost identical to the 0.2.0 version, except it is a Python Product. You still have the full source, but a choice of how to install. To install ZRTChat-0.3.0.tgz, expand it into your [Zope] directory. There are still a few features I want to put in, but I thought I would release what I have before I get distracted with other things.

ZRTChat 0.2.0 and earlier is a product made from ZClasses. It's provided here as a .zexp Product (source code), so anyone can see how it was done by blithely, irresponsibly, simply, merely, unscrupulously, unceremoniously, unashamedly importing it into the Control_panel/Products folder. It provides a (Real Time) HTML chat forum. It's usable out-of-the-box. It probably could use some some scrutiny for efficiency, etc. It employs:

1. ZClass
2. ZClass within a ZClass
3. Cookies
4. Frames/noframes
5. Creation of ZClass instances programmatically
6. Forms
7. RESPONSE.redirect()
8. Very little JavaScript

To use, copy the file into your [zope]/import folder. Within Control_Panel/Products in the Zope management interface, click the Import/Export tab, and enter the filename, ZRTChat.zexp. Since this is a ZClasses-based product, it requires Zope 2.0+. It will use your standard_html_header and standard_html_footer, so you might want to override those from the default.

Here is a screenshot of 0.40 with a chat in progress.