I scored myself an APC Backup-UPS RS 500 the other day. It’s a small unit designed for running pretty much one machine on it.

The nice thing about this is that it has a USB interface which I have connected to my server hosting andybotting.com, and allows me to monitor it using apcupsd software. It even comes with some basic CGI scripts so I can monitor it online. If there is a power-out, then the UPS alerts the apcupsd, and at a certain point, can instruct the server to gracefully shut down.
Although, my ADSL modem isn’t plugged into it yet because it uses different plugs. I need to find some way of converting the IEC power socket to something I can plug my Australian power plug into. One possible solution might be a standard 4-port powerboard, but with an IEC plug on the end. I can’t say I’ve actually seen one though.