Did you ever want to create groups for your subscriptions, sort of like a playlist, where you can classify your channels into certain sub-categories, and maybe clean up the list of your subscriptions? YouTube is now playing around with a "Collections" feature which allows you to do just that. If you go to your "Manage Subscriptions" option on the left side of your feed, you'll be taken to a page where you can do a whole bunch of stuff: select which channels you want e-mails from, select channels where you want to see only the uploads, and now, an icon that allows you to put your channels into different categories.
YouTube Collections: Create Classifications for Groups of Channels
When you go to the Manage Subscriptions page, you'll see this:
When you click on the blue button, you'll be taken to a screen like this:
I entitled one called "Epic" that now shows up in the subscriptions list. When I click on it, only stuff from Epic Meal Time and Epic Rap Battles shows up. It's a neat way to organize your subscriptions, because those can be super long to sort through at times. So if you want to classify something as "music" or "comedy" or even deeper sub-categories, you can now do some house cleaning. You'll just have to remember where you put it, though. As always, you can remove it from the list and do whatever you want with it if it doesn't work out.