Create a Google Custom Search Engine on the fly

Always wanted to be able to run a search over a limited set of sites* at once? Google just made that really easy: by giving it the URL of a page containing links to other sites, it'll create a dynamic Custom Search Engine that will search just those linked sites. More information.

It would be nice to be able to delimit certain parts of the page to use as CSE links, like you can for AdSense.

* I'm sure there was more discussion about that - with FOAF? something Michael Fagan wrote? can't find it at the moment...