For battery backup power on my home network (which, among other things, is hosting this site), I use APC SmartUPS systems. Currently I have two SmartUPS 1000's (SUA1000, the older model) and a smaller 450VA unit for the main switch. I bought the two 1000's used from RefurbUPS.com.
SmartUPS 1000 Runtime
The following is some runtime data that I extrapolated from the APC specs on the SUA1000:
I have a short page dedicated to the AP9605 PowerNet SNMP SmartSlot card.