A spell check similar to the one at digg would be a good feature here. There are a lot of people on the forums here that misspell many words. Some are so bad that I don't even understand what they are trying to say. It may be because their English is not fluent or for whatever reason but a spell check would definitely be useful her in my opinion. I personally don't need it because Firefox lets me know if a word is misspelled but it would benefit those who don't have that.
i have a spell check on my browser. you don't? consider all the posts being made at the same time. all the users here reading and whatnot. now consider the added load of checking everyones mistakes before they post. probably won't see a spell checker here.