[Zope] Progress information for long running process

[Charlie Reiman]

Just to chime in another option:

If your clients are not techies and want a status bar, it would be quite
easy to establish a small status bar as an image, then refresh it via
javascript. Zope can respond with an image whose width attribute is
proportional to the percent complete. If the task is complete, Zope can
respond with an entirely different image, saying 'Done!' Zope could also
respond with an error image.

This would give you a pretty status bar and a relatively low load on zope.
If it were me, I'd probably do this if the task took about 5 minutes. But if
it took more like an hour, I'd go with the external email.