rossco
UPS's can be a false sense of security some times. I've had power surges kill machines that are on a UPS, either because they were basic units, or because the surge came through other devices. Phone lines, tv arials, network cables, power spikes can come in from anywhere. It's Murphy's law.
Some good info there Rossco
A good (higher end) UPS system will have sockets for network and phone cables.
I think UPS systems are like home security: Nothing will ever be guaranteed 100% effective. Just depends on how far you want to go.