Answers.com double-click

A few weeks ago I mentioned word-selection by double-click.

I have discovered that Answers.com improves on this with a rather nifty hidden feature: if you double click on any word on the page it will immediately look that word up in Answers.com using AJAX!

This looks very innovative to me. Using the rich Javascript API to augment the browser's existing functionality is very pleasant, but here the product is a dictionary/reference site that is totally cross-linked! Poor old Wikipedia seems rather limited by comparison (though, to be fair, there are massive advantages to conventional links. This technique is not a replacement for that).