It's a far from novel idea, but In an attempt to use my quality time (such that it is) more productively, I now only use social media on handheld devices. It's a move I've been contemplating since December last year, when I had a number of different things going on and felt weighed down by 'PC Pressure'. Sat at the computer, roaming aimlessly online, countless windows open and not doing anything in the process, let alone the things I should actually have been doing.
So now, computers are for doing stuff and mobile is for downtime stuff. If I've 15 minutes to spare, I'll check in on Twitter. Waiting for some files to render? I'll do a bit of planning on Trello. I repeat, this is not novel, but to me it's a breakthrough. I've also stretched this concept a little to try and get as much done as possible on phone and other mobile devices.