A neat trick I found while wandering the Interwebz...
This uses the free iPhone app "Starbucks." So, start by downloading the Starbucks iPhone app from the AppStore. After it finishes downloading, put your icons into "wiggle" mode (press and hold them until they wiggle).
Now, you'll do the normal process of creating a folder, but use the Starbucks app to do it. Press and hold the Starbucks app and move it over another icon. Once a folder is created, notice that a folder name does NOT automatically appear:
After creating the no-name folder, press the Home button to stop the icons wiggling. And, that's it. You now have a folder with no label. And, if you put the icons back into wiggle mode, you can add any icon to that folder. You can also take OUT the Starbucks app and the label not appear.
You can repeat this process as many times as you wish (make a folder with the Starbucks app, put at least one more app in the folder, take out the Starbucks app, make another folder ... etc and ad nauseum). See?
One thing - if you put any text in the folder label field, even with the Starbucks app in it - that text stays and you can no longer have a blank label for that folder. No buggy, cause you can just make another folder. Just so's you know.
Pretty cool, eh? I for one, NEED folder labels because otherwise I don't know what's in them. But - maybe some of you will like this.
P.S. This "trick" also works on a jail broken iPad. But, the pictures come from my Mom's stock iPad2 running iOS 6.1.3 (I hear this trick also works on iOS 7). And, I don't know how long this ability may stay or who's got the bug in their software, Apple or Starbucks. But, for now, it works right neatly.