Google extends custom search: even easier to create and embed

I've written previously about Google's Custom Search engine:

• Google Custom Search with Bloglines Search OS X mashup


• Google delivers custom search pages


• Search gone mad - Custom AJAX API search

I like it, even though the last time I tried it the "use all URLs on this page" function was flaky and didn't work with JavaScript generated content. (See: my current custom search collection)

Now Google has added new "on the fly" searching based on page links. Google Blogoscoped has some examples including del.icio.us integration.