1. FocusWriter:



"FocusWriter is a fullscreen, distraction-free word processor designed to immerse you as much as possible in your work. The program autosaves your progress, and reloads the last files you had open to make it easy to jump back in during your next writing session, and has many other features that make it such that only one thing matters: your writing."

2. Darkcopy.com:

Same as above, except on the web.

3. And for those entering NaNoWriMo: NovProg2



"NovProg2 allows you to create a graph of your progress in writing a NaNoWriMo style novel. You enter your wordcount and it updates a graph showing you how much progress you have made. It also shows you how far you are through your daily goal, and your total goal. Mousing over a bar in the graph will show a tooltip with that day's wordcount."