Source for Ipe presentations in Wiki/Showcase

Hello,

I'm hoping to use Ipe for presentations, and the example PDF files in the Wiki look great. I'm wondering if it might be possible to obtain the "source", i.e., the necessary .ipe, .isy, .lua files for some of these presentations.

Without that, I don't have a very good idea about how/where to start.

Thanks for a great piece of software!
-mandar.