Chrome - Notification bar overlaps with the browser UI, that way it can be distinguished from fake bars.
Chrome - Drag the little globe from the Google Chrome address bar to another browser to open the page in that browser.
/via Carlos Arellano
Chrome - Status bar shift down with the cursor when it is hovering a link near the bottom of the page. After a few seconds its hows the entire URL.
Chrome - Marks the position of cmd-F search matches on the scrollbar.
/via Saul Cozens
Apple - Menu drops down and bounces a little bit. Search bar expands intelligently once activated and shows different search results depending on what page you are on.
/Thanks to Renato for being the first to submit.
Chrome - When closing tabs in chrome, the position of the close button remains the same on both sides.