I've been in a slump several times and this is what works for me. I usually give it a little bit of time, then I just make myself pick up a project, figure out what needs to be done, and then finish it. Usually it doesn't take long to finish and then I pick another one and so on. After a project or two I'm back into the quilting mood. One time I made a list of my UFO's and then asked my DH to pick a number between 1 and 10 and whichever number he picked, I finished it.