I'd like to use Google Custom Search to create a custom search engine that anonymous users can edit (by adding or removing sites to the custom search engine). Is it possible to do this?
It seems like it is possible to do pragmatically, though i didn't try. Here you can find bit more about it. Basically, this is what I get from that page. You can have an xml file on your website, that google will query and will show results from that file only for you custom search engine. Now all you would need is an interface to have that xml file manipulated easily, though nothing stops you from editing it manually. :)