Use your phone to capture an image that you like. You can browse straight to this site on your phone, and upload the image directly from there. Receive the email on your phone, and post the resulting image directly to Facebook without ever sitting down at your desktop or laptop.
Having trouble getting started with that canvas you always wanted to paint? Just upload the image that you're using for inspiration, and use the stencil to paint the first pass. You'll be surprised at how quickly the rest of it goes.