I have a detatched garage with power that was a nightmare to get to in the dark. Tried a PIR light but it drove the neighbours mad. Trawling the web I came across a wireless light switch called Freeswitch from a company called Sensormech. The unit comes with a receiver that fixes to the wall next to the light and does the switching and a radio sender module that is small enough to fit onto the back of a regular light switch. I can now switch the garage wall light on and off from the kitchen - fantastic and all for less than 80 quid. The web site is
www.sensormech.com
www.sensormech.com