Opera shows real-time thumbnails of the selected pages and lets you reload them at a custom interval so it's a cool way to monitor changes.
There's also a link to Opera developer tools, a list of bookmarklets that add some of the best features from Firefox's DOM Inspector and the most popular extension for developers: Web Developer Toolbar. You can inspect, edit or remove DOM nodes; view, edit or disable stylesheets; view HTTP headers and cookies. It looks pretty impressive for a JavaScript bookmarklet.
Opera finally becomes a normal browser: if you enter a query in the address bar (something that's not an URL or a single word), Opera performs a search.
