The best skill I learned to smash writer's block was a good idea. Since those do not come along every day, you will have to let me know your little tricks.
The two things that work for me are:
a) Just keep writing, one word at a time, even if it's so boring I could scream - until I find the story moving again (easier said than done, I know). Then I go back to delete what didn't fit if necessary.
b) I sit and write stream-of-consciousness style about the story. I'll take a notebook and brainstorm about the story, pointing out the holes and throwing out ideas on how to fix them until I find one I like enough to run with it. For last year's completely goofy story, I have pages of things like "Why would the Toaster of Doom use llamas to do his dirty work? What is it about llamas that makes them ideal henchmen? " Etc.
This year I'm writing slightly more serious stuff, but the brainstorming works about the same...