Flywheels are used in large data centers to cover short power gaps like yours, or to allow time for a backup generator to come on line. They are (typically) only good for 45-60 seconds, and they are expensive, but they have a longer lifetime than UPS batteries, and can make sense for a very large data center.
Another approach was Google's, who integrated a small 12V battery with each rackmount server. The motherboard runs off of 12V input only. This approach works for short, several-second power outages (like yours), for longer outages it only serves to allow a graceful shutdown. It also works if you are large enough to order custom motherboards. :)
Now that we have these unlikely alternatives out of the way...
For most small to medium size data centers, UPS systems make a lot of sense. Start complaining to management now, so when the data loss occurs, you can put your "I told you so" hat on and demand the UPS money, instead of just being on the defensive.