Opera may have switched to Google's Chromium to handle the heavy-lifting of the web, but that doesn't mean the browser isn't doing plenty of work to separate itself from Chrome. It comes with experimental features you can activate if you're feeling brave, including the recently-added "video boost" for the software's "Turbo" option.
"Opera Turbo" is basically a compression proxy, much like that found on the mobile versions of Chrome. However, the video boost option funnels content from sites such as YouTube through this service also. The theory is that you'll get your moving pictures a little faster, connection permitting.
gHacks' Martin Brinkmann gave it a go, but his 50Mb connection is obviously more than good enough to handle even the most high-definition of videos.
Brinkmann mentions the boost feature was added to Opera Coast, the company's new mobile browser, though it's also appeared in the desktop build in disabled form.
While he may not have seen much benefit, for us in Australia (especially those subsisting on less bandwidth) it might be worth trying. You'll need to grab Opera, type
opera://flags into the browser's address bar and track down the settings for "Opera Turbo" and "Video compression in Opera Turbo".