I live on the gold coast, in a new area, and we have the occassional power flucuation.
Blown fuses on pinnys and a blown up Hard drive in my Star Trek Voyager Machine was the result of the last power flucuation, costing me plenty. $
Anything from a surge protector (at the device) or a RCD, if cheap to purchase, CANT HURT. I understand what Mike(Homepin) is saying, but any extra technology that may safeguard you against financial or personal injury, when it comes to electricity, cant hurt.
p.s- I watched Beaky electocute himself oneday at a Security Install from a light switch. To this day, watching him SCREAM and swear and totally freak out, still makes the both of us laugh (espescially me). 
(he will kill me for mentionng this, but gee it as funny at the time).
They say Electricity is like your x-wife and $maintainence, once it gets hold of you, it rarely ever lets go. ! 
thats why if you have light switches with metal faces and home made mounting brackets you should have an RCD on your lighting circuit also.
And as far as compulsory RCD.s go I am all for it. 15 years ago I was working under a 1500 litre fish tank with its on switch board. I knocked a pipe which broke and water poured all over the switchboard and on the ground. If it wasn't for the RCD which cut the power I would have been kneeling in live water.
Any way, if you have an RCD at your switch board then there is no need to put one on your pins
