I had written this hack a long time ago, but considering the renewed interest, I wanted to make sure it was recorded. It make a small row of clickable smilies show up on top of box where you edit your post. Click on the smilie and it gets translated and put in the right place, no more guessing! Here is the link to the hack.
*Edit* The hack has been fixed for use on comments which show up on the main page (without the use of 12_comments popup)