I wrote the following after being a little unhappy with current solutions. It still need a bit more work, but overall I'm happy with it. I'm distributing the code under MIT license so use it however you see fit. I only ask that you let me know of any problems or suggestions on changing it. It's not a condition of using the code, though. Only courtesy.
Something like this might be useful for a web based OLC. :p
Oh, it's in coffeescript and scss. I suggest if you want it totally cross browser compliant to use compass with scss, but you could totally just compile it to css and js and drop it in if those technologies aren't of interest to you.