SSD (Solid State Disk) devices are becoming very popular and are slowly replacing traditional hard disk drives, particularly in notebook devices. While the SSDs are fast, lightweight and quiet, they are still relatively expensive, although prices continue to fall. It has also come to light that such drives do not do well when the power is interrupted - it's not so much file system corruption (as may happen to a traditional hard drive under such conditions), but rather serious or fatal physical damage to the device itself - even in high-end "enterprise" devices.
The magnitude of this potentially disastrous scenario (the SSD device losing power while it is performing a read/write operation) has now been documented, and the scope of it is quite serious. Pretty much every brand and model of SSD tested - except some Intel devices - suffered catastrophic failure in these tests. Ouch. While this test had a small sample of drive models, they all included some form of "power loss protection" - a new technology supposed to prevent just this sort of problem. Obviously, some work to be done there.
In a laptop computer this result would be unlikely, because they can run from battery power if their is no AC power, and will power off or hibernate before the battery completely drains. With a desktop computer, it makes a great case for using a UPS (Uninterruptible Power Supply) to protect your data. A UPS will start beeping like crazy when the AC power to it goes out, but its internal battery will allow you a reasonable amount of time (10 mins or more) to shut down the computer properly and avoid potentially damaging something - particularly the SSD.
A UPS will also isolate the computer from electrical brown-outs and power surges - always a good idea. Note that the UPS is different from a "power strip", as the UPS will actually allow power to continue for a short time after the AC power is lost.