Ability to save key bindings as a single file.

As a VERY left handed player, I've re-bound almost every key in Minecraft.  I LOVE having all my movement keys mapped to the number pad for example.  It's natural and comfortable and I don't have to think about or even look at the keyboard.  It's GREAT! 

But, my kids AREN'T left-handed.  So, every time one of us plays we have to go through the settings and individually change each and every key-bind back to our own personal preference.  That's ridiculous!

The developers seem to be operating under the assumption that every player has their own computer and no computer is ever shared. 

Individual, personal settings like key-binds should be storable as a file, so we can take our settings with us and change them quickly and easily, and not tied to the computer as if every person was the same.

It seems so obvious and logical to me that I can't believe it's never been addressed before now.