I definitely have that problem. It helps to actually have something planned ahead of time that you can work from. I have a hard time when I wake up and just decide to post and come up with something on the spot. In particular, I find that my posts are of better quality if I run out of time halfway through and finish them later, or if my browser/computer/ceiling just crashes on me. That way I am forced to redo it, and usually for the better.