Have you ever traveled to a different city, country or environment and all of a sudden you're so much more aware of your surroundings? You seem to have more ideas and energy? Yes, I'm sure that a big part of it is just being out of your normal "have to's" but a bigger part is about seeing things from an unfamiliar angle.
The musician Brian Eno created an interesting approach called Oblique Strategies...over one hundred worthwhile dilemmas. Brian originally created the deck with his friend Peter Schmidt (a painter) - it was a basic set of working principles, or strategies, that could help jog their creative minds/energies when they were in the studio and the pressure to create was on. Here's an online version of it.
The deck itself had its origins in Brian's discovery that both he and Peter tended to keep a set of basic working principles to guide them through moments of pressure - either working through a heavy painting session or watching the clock tick while you're running up a big studio bill. They both realized that the pressures of time tended to steer them away from the ways of thinking they found most productive. They used the Strategies as a way to remind themselves of those habits - a way to jog their mind back into productivity.
Here are a few strategies to help you get unstuck and thinking creatively again:
Blindfold yourself and "look" around your room until you find an object you can't remember - make a shot about this object.
Pick a time of day, tell yourself a story about what happened then - make that image.
Think you need to look through the viewfinder (or rear screen) when taking an image? Not so grasshopper! Try shooting from intention rather than obsession - just point the camera towards the scene you're drawn to and press the shutter.
Close your eyes and draw a portrait from memory.
Go to Home Depot and find an object that totally baffles you. Make up a story for it.