A bit about indexing geo-spatial data and reverse geo-coding, with a Flickr slant for the web2.0 expo.
Obviously not having me talk over the top of it doesn't help too much, but imagine it's great.
Oh and if you need any takeaway point it's this. You probably don't *need* to do spatial indexing until you hit around 50 million objects.
Clipping is a handy way to collect important slides you want to go back to later.