I've used these and recommend them: Power Strip Liberator Plus Extension, they are available from a variety of places but I found a good price on ebay : http://stores.ebay.com/Great-Lakes-Mercantile They provide a 6" pigtail so that a transformer doesnt take up multiple outlets and they also have a pass-thru feature so you can still use the outlet its plugged into
Ditto... I had a surge protector plug into a 2 socket wall surge protecter for 2 years at an old victorian house that had the electricity slam off and blast on 5 to 6 TIMES A DAY for 1.5 years - never had one PC problem ever...
I won't pretend to know anything about electrical stuff but I have witnessed several online "discussions" between folks that appear to know what the hell they were talking about and based on that its my understanding that most cheap (<$20-$30) multiple outlet surge protection power strips have minimal if any real surge protection and therefore there really isnt a problem plugging one of these glorified power strips into an UPS. Some useful info here: http://www.pcguide.com/ref/power/ext/protSurge-c.html I can't see how it would hurt plugging a surge protector into an UPS but I think its wasted money because I would suspect that most UPS's have better surge handling than the typical standalone surge protector. Just buy a power strip if you need more outlets on your UPS.