Windows/Mac/Linux: Opera, our favourite alternative browser, added a new dev-like channel today. Dubbed "Opera Next", it will give you a chance to test out all the latest features, at the cost of a little bit of stability.
Like Firefox's new Aurora channel, and Chrome's Dev or Canary channels before it (ah Chrome, you trendsetter), Opera Next is an separate installation of Opera that lets you try out the latest and greatest features, without messing up your current installation. It's a bit less stable than the other versions, as expected, but it's a nice way to get the newest features sooner.
Opera previously released alpha versions on a somewhat regular basis, but this channel will let you run both side-by-side, update on its own, and let you use a separate profile if you so choose. Opera Next is a free download for Windows, Mac and Linux systems.