Ah damn, I was too late to think of posting this too. My alias/symlink variant at least makes a virtue of the fact that it shows up at the bottom of the fanned-out stack. After all it's an awful long way to the top of the fan to actually open the folder, so, how I did it (in Terminal) was simply:

cd ~/Downloads
ln -s . ' Open Folder '

And sort the stack by name. That's it. Repeat for any folders on the stack of course. Yes, you get the symlink/alias arrow, but I don't mind that; after all it *is* pointing to the folder rather than being the folder itself...

Naturally the text can be anything but starting it with a space should put it at the front (unless you've done some of the aforegoing suggestions as well and have just ' ' as the filename).

(ah, I missed diamondsw saying basically the same thing. :-)