One of the more ambitious features shown off for the PS4 prior to release was the "friend assist" feature. Say you're live-streaming your playthrough of Knack, as pictured above, and you get embarrassingly stuck on a section, any of the players watching can jump in and help you out via remote play. It's a novel feature and hasn't been properly explained yet (can you invite a friend to assist even if you're not live-streaming, for instance?), but the potential is truly awesome. Granted, I for one would be unlikely to use this feature often, given that I don't get the same sense of accomplishment from having someone else just take the controller for me, but it's a very interesting, truly next-gen feature that I imagine many would make great use of.