When I find myself in a bit of a pickle plotwise, I back off and go do something else for a few days. I can’t force the story. I have to figure out what’s happening in the background (and no, I really have no more idea of what’s going on in my stories then the main characters do). Once I’ve got that in hand (and this may force the odd rewrite to what’s gone before),the next set of scenes pretty much write themselves. It’s fun, actually, to see a story pull itself together.
Yes, I have to sit in front of the computer with my fingers on the keys, but I spend just about as much time correcting my mis-typings as I do getting the words down on paper. The words are already there, lurking somewhere in the back of my mind, ready to leap out onto the monitor as fast as I can hit the keys.
It really is fun. That, and research. Research is fun, too, if you do it right.