Best Buy offers the APC 650VA Battery UPS for $39.99+Free shipping. This Uninterruptible Power Supply offers 8 surge protected outlets with three outlets backed up by power. IT also has phone and ethernet surge protection. It is covered by an APC $75,000 3-year equipment protection policy.
These won’t keep your PC going through a long power outage (most outages are short) but it will give you an hour or so to shut things down.