4K video support is still pretty new, and it can be costly to get for your home theater.
Yourcomputer is another story.
With a decent enough graphics card and monitor, all you need is content.
YouTube can provide that with Googles TestTube program.
Much like Google Labs in other Google properties, TestTube allows adventurous users to try out new YouTube features.
Currently, there are only two features.
With this activated, users can stream 4K video in up to 60 fps where available.
Google even has a selection of videos you’re able to start with.