I personally don't see much value in a UPS, unless it is a computer. A UPS can prevent data loss on a computer. Not too many ways to lose data on electronic stuff...
On the other hand, the benefits of surge suppression are hard to ignore. To ensure a clean audio and video signal a line conditioner can also be very beneficial (the expensive part).
My old surge suppressor was a low priced Monster unit that offered some basic line conditioning (about $90). I made the mistake of buying this with the TV at Tweeter and new ones can usually be had for about $65 from Amazon (HT800, etc.).
I just spent about $6K on my new home theater setup and decided to leave the old one on the Mitsubishi RP and get a slightly nicer one. I really liked the integrated look of the rack mounted units, even though I admit it is overkill. I was looking at the units from Panamax and Monster. I decided to spend close to $200 on a nicer unit.
Anyway, I stumbled across a deal I couldn't refuse. I found a stage 4 Panamax 5300-EX for only $249. These retailed for $550 and are simply last years models. The new ones offer more lights. I bought from here:
http://www.soundcity.com/ (shipped same day)
www.panamax.com
http://www.panamax.com/Products/A-V-Components/Default.aspx
(retail price list on lower left)
http://www.monstercable.com/power/
(explanation of stages)