Daily Wordcount Calendars. For those of you who want to be uber-organized. Me? I'm somewhat laid back about word counts--yes, I check the word count after I've written a scene, but I don't obsess about how much more I have to do.
Generators, character sheets, etc. I do the barest minimum of character sketches before I start on a story, but name generators are always useful.
Organizational software: EverNote and FreeMind. I've seen these mentioned in the forums. If your thought processes aren't particularly linear, these might be useful for you.