potentially cool software...

So, a little while ago, my cousin emailed me with a link to this software that helps you organize your script(s). I haven't had much time to look at it, but it seems to help you organize your notes - you could put a note saying that you need to find a certain prop, or perhaps a note about a plot point you need to improve on later. Here's the link:

http://www.celtx.com

If anyone has any experience with this software, please let me know what you think. I'm not much of a writer right now, but I'm trying to get more into it. Any information anyone has about this software (or other software you'd recommend), I'd really appreciate it. Thanks.