You can switch GNOME Software to manual updates, or block offline updates completely with polkit. Neither solution is perfect. The GNOME developers have no interest in improving the situation.
Recent releases of GNOME on Ubuntu, and presumably in other distributions as well, finally support remote access to your GNOME desktop on both Xorg and Wayland from a VNC client. However, they do not allow you to connect to your desktop when it is locked, and similarly if your desktop locks — either because you… Read More: Convincing GNOME to allow remote desktop when screen is locked »
UPDATE [2013/01/08]: As of the recent Galaxy S III update to Jelly Bean (Android 4.1), most of the text below is obsolete. The connect-within-3-seconds limitation appears to no longer exist, and you can connect to and disconnect from the phone multiple times without unplugging and replugging it. I’ve tested mtpfs, go-mtpfs, and simple-mtpfs with my… Read More: Using the Samsung Galaxy S III with Linux »