Al-Muhajabah's Movable Type Tips

Live comment preview allows commentors to see what their comment will look like as they type it. It's a neat trick, although it works best if you have your comment posting form on the individual entry archive page or otherwise do it from a full-size window rather than in a comments pop-up.

Start here, but modify it according to this if you have "convert line breaks" on as most people do. The modified version of live comment preview will fake the line breaks. Otherwise they don't show up and when people try to insert them, it messes up the actual published comment.