The ability to share folders with people using Dropbox has been a life saver. However, this only works if the other person has Dropbox. I find most people these days have the service, but it’s still a little awkward setting up a shared folder with them if the content you are sharing is only temporary.
Now, the ability to share a link to a folder instead, and have this dynamically update with the new content you place into the folder is an incredible tool, and one I can see my self using almost daily.
Check it all out at http://blog.dropbox.com/?p=1138