No, I'm not talking about the many easy, well-known methods of using your gadget as a "remote control" unit to advance slides on a laptop or to view PowerPoint slides on the device itself. Most iPod users can figure out how to show pictures on a TV. And Windows Mobile devices are easy to use for presentations -- they even come with PowerPoint Mobile.

I'm talking about hard-core mobile presentations using your iPod, BlackBerry or Treo; starting with your PowerPoint slides and presenting on standard business projectors -- without a laptop.

Why would anyone want to do such a thing?

There are legitimate and practical reasons - including:

- Using your gadget as a last-resort backup in case your laptop fails;