[Zope] Uses of METAL?

Hi all, I've a few things with Zope so far, mostly using ZPT and python scripts, and I haven't found any serious uses for METAL. In almost every case that I've been tempted to implement METAL, I've found I could accomplish the same thing with ZPT and/or python scripts. My question is: How are other people using METAL in serious applications? I would love to hear how it is being used by those more familiar with Zope than myself. Thanks very much, Alec Munro