This is my second coif, much more battle-worthy than the first although I still wouldn't trust my life to it.  It has a full mantle, and leaves very little of the face exposed.  Nonetheless, it is fairly comfortable, although jaw movement is somewhat impaired and it is very difficult to eat while wearing it.  Yes, I have tried.

Update: 9/17/05

I have modified the above coif.  There is now a flap on the chin that I can unhook if I want to.  Basically it allows me a greater freedom of the jaw, but I can still loop the flap onto a hook attached on the side of the coif for better protection in battle (not that I am actually going into battle with this thing, but it's nice to have the option).  This is a more or less authentic design; you can see something like it in the movie Kingdom of Heaven (2005).  That's where I got the idea.

Rings:

16 ga. 3/8" ID
Galvanized Steel
In the European 4:1 Expanding Circle weave