Google is celebrating its 15tth birthday with a worldwide doodle featuring a playable game where you can hit a piñata by clicking on it with your mouse (or using the space bar), and gaining candy for points.
Google also has an easter egg, where if you search "Google in 1998," you'll get a classic look for the search results page.
Google is 15 years old this month. This easter egg reveals how Google used to look: https://t.co/CvLOJub7zA
— Matt Cutts (@mattcutts) September 26, 2013
Also in celebration of its birthday, Google made a handful of search-related announcements, which you can read more about here. These included the biggest change to Google's algorithm in twelve years.
Thanks to Simon Rüger for the video.