I've been trying to avoid posting tons of Ajax/XmlHttpRequest/Web 2.0/whatever applications that are popping up everywhere like mushrooms but this one got my attention. It's basically a version of the Mac's Spotlight feature for the web and on the web, it even has it's looks. It's nice, check it out.
On the same line I found (and I think João Pedro had mention it to me before, now I realize that this is what he was bugging me all day with script.aculo.us. A good decent .js lib with a lot of activity and community work to save hours of hard work with your first Web 2 applications.
Another patent related war that turns out can take off the market (US at least) one the most successful mobile gadgets of all times, the RIM Blackberry. Let's wait and see how this develops.