Vimeo will let you download (but not stream) 4K videos
YouTube embraced 4K video a long time ago, but Vimeo is at last catching up... well, more or less. The internet media hub now lets you download 4K clips from both Vimeo Pro members and Video On Demand providers. If you just snagged a Retina iMac or a lower-cost 4K display, you now have one more source that will do justice to your extra-sharp screen. However, there's no streaming here. As Vimeo explains, it's waiting for the technology to make this technology work -- not many people have 4K-capable displays, and internet connections typically aren't speedy enough to deliver that many pixels in real time. Even so, it's an important upgrade if you've been meaning to watch Video Game High School and other online productions in the highest resolution possible.
