Figuring out how to search the current site

A bookmarklet for searching the current site (using Google), that my buddy over at Splorp came up with, inspired me to think about how to provide a way to tell software how to use a website's local search engine.

So, I've launched a discussion/project on Search Query Interface Discovery. My hope is that it'll provide a standard way to identify local search engines that can then be used by tools like my buddy's bookmarklet - or maybe even be built right into web browsers.