Pick a random object in your house and write 200 words about it
Find a different place to work. If you’re at home, try a coffee shop — or vice versa
Take a bubble bath
Call a writer-friend and commiserate first, then assign one another a writing project to be completed within a few hours
Try outlining your novel/essay/article, if you haven’t already done so
The above article gives you some great ideas for combating writer's block.
However, you can always look on your block as an opportunity: to learn more about yourself and your writing.
Start by becoming fascinated with your block. What does it mean? (Resistance to your writing always means something.)
Write, by hand: "Why am I blocked?" Use a timer, and write responses to that question for five minutes.
You may find that just writing your responses clears your mind. The block may be gone. If it isn't, you'll still discover why you're uncomfortable. That may be due to something about the piece of writing you're working on, or something else.
Fix the problem, whatever it is, and you'll be able to write.