Are you certain about that?? (I remember learning in my Oracle classes that it does make a difference...)
why in heaven's name would it even occur to you to move it?
I created my table with the fields in "Order of Importance".
Now I think it would make them easier to work with if they - or some - were in "Order of Process Flow".
For example, you have an "activation_code" before you would have a "temp_password".
Likewise, you need a "salt" before you can create a "hash".
It is a minor point, but detail matters!!!
Anyways, I think that the Left-to-Right Order of your columns does affect query speeds... (I think it is how the database stores the data and accesses it in "memory blocks", but who knows?!)