Gemara Shabbos 49a mentions a story about Elisha Baal Kenafayim who was saved by his Tefilin turning into dove's wings. Magen Avraham Orach Chaim 28:4 says the Minhag is to wrap the Tefilin like wings. How would you wrap your Tefilin like wings? Is this a Minhag that is still practiced?
It is. See the Moroccan Way of wrapping tefillin from about 2 mins in. The commentary is in French but the pictures are sufficient even if you don't understand French.
I have seen some of my British friends in the UK do it this way too.