Impossible? No, just unlikely.
The medium length Langdon Ambigram displayed to the left is a nice generic design that makes you do a double take.
This preview shows that this design says 'Langdon' one way and also says 'Langdon' the other way.
Roll your mouse over the design to the left to see it rotate.
All items in the FlipScript store are already displaying the Langdon Ambigram. To see them, click on a category in the red bar above and the Langdon Ambigram will appear on everything you see.