Desktube is a straightforward AIR-based application which allows you to search for, watch and manage YouTube videos, even if you don't have a browser. The authors claim "this allows desktube to be extremely fast in comparison to other websites because it eliminates page load times and browser dependencies".
The program's main interface certainly loaded quickly for us. A "Search" area in the bottom third of its window displayed 15 "recently featured" videos; clicking one of these launched it in a viewing pane, while a third pane on the right displayed the video rating and description, along with "Subscribe", "Favorite", "Share" and "Playlist" buttons.
And right-clicking in the Search box displays options to copy the video link and view "more videos from this user", along with options to view the video at half the regular size, normal resolution or full screen.
You'll probably want to jump straight to a video of your own choosing, though, and the easiest way to do that is via the search box. Enter a regular YouTube URL here, or a key word, and thumbnails of any matching clips quickly appear. You can scroll the viewing area if you need to see more, and clicking any thumbnail launches the video immediately.
And further tabs to the right of the Search option allow you to view and add comments, look for related videos, and manage your playlists, subscriptions and favourites (you'll be prompted for your login details as appropriate).
There are a few issues here. Desktube can't view every YouTube video, for instance, although the vast majority worked just fine for us. And searching is relatively weak; you don't get suggestions as you type, and you can't filter the results. At all.
If you're just intending to browse your favourite channels, though, this may not be a problem. And while we're not quite sure that we'd describe desktube as "extremely fast", it does feel quicker than browsing YouTube in a regular browser.