A lot of forums and boards provide very small textareas for new postings. If you type a longer posting, you have to scroll up and down, to read what you have written and to proceed. This situation is annoying.
Now here is my solution: Resizeable Textarea extension. It lets you resize most of those textareas.
Firefox 4 with build in resizing is out!
Use it, this Extension will be no longer supported and developed.