I've been trying to make myself get up early and spend a little time working on studies before I go to work. Mostly I've been using Panoramio to find landscape reference. I try to keep most of them to thirty minutes or so, but here are a couple I enjoyed enough to spend an hour or two on.
I also discovered a great Tumblr blog for facial reference -
Not ideal if you're looking for dynamic angles or lighting, but great for practicing skintones and looking to study different facial features. Like a lot of artists, I catch myself painting the same faces over and over so this is good practice for me.
I also tried to make myself get up a little early to go for a run on alternate mornings. That...has not worked out so well. My motivation to go outside and move my feet is apparently at an all time low first thing in the morning. But it does make getting up to sketch, knowing I can stay in my pajamas, much more appealing!