I'm not sure how that would work. First off, I think when we use an actual uploaded pic ( from our own PC) that would be taking up bandwith here and that would cost Anne. Also, I'm not sure if its even available to be done like that.
I'll let Anne know to come on in here and address this with you, Lorie.
In my humble, somewhat technically-constrained-knowledge opinion: The problem with that is that your PC would need to be turned on and connected to the internet at all times. The pics attach to and remain with your signature with each post, and the pics would need to be located on a network that is accessible to the internet. You would be opening up yourself to all kinds of hackers and viruses if you did that.