I found this thread because I want to know what a certain icon means exactly in my notification bar. It isn't any of the icons in the image Phases posted.
It's circular, with two arrows "orbiting" the center of the circle, kinda like a refresh icon of some kind.
Similar to this, but without color:
Now, I'm no idiot and I can come up with several things that it CAN mean, but I want to know officially what it is for and why it comes up once in a while.
EDIT: Sorry if the image is really big. I resized it within my post but apparently it didn't work.