Meet Seymour. He's your personal typist.
As you type anywhere on the web, Seymour keeps count of the characters that you write. Seymour can remind you to reduce the length of your paragraphs and can even prevent you from crossing a certain amount, set by you individually, for each website that you visit.
Seymour is unobtrusive and only shows its counter sign when you're writing. You can easily turn on or off Seymour for a certain website and can easily choose, for each website, a limit of characters you'd like to set for your self.
Seymour will take care of the rest for you: he will show you character count with a light color change - starting from basic black to red as you get closer to your limit. This would help you grasp how much you've written.
If you choose to force that limit on your writings, Seymour will also show you that limit in its bubble and how many more characters you have left until you reach it. When you do, Seymour will forbid you from writing more in that text area. This is a nice little feature to help you stand in your own expectations.