interesting feature @ the nytimes site
Feb. 19th, 2007 08:11 amInstant Dictionary. Double-click a word and a pop-up (unfortunately, full one rather than an ajax one) shows up with a full definition from the American Heritage Dictionary. Only works on articles, not the front page. Don't know if you need an nytimes "free account, blah blah blah" for it to work, as I have one.