Following a near death experience at the hands of an illegal immigrant and his gang who suddenly tipped out of the back of a lorry just north of J9 of the M3 in Hampshire (clearly they're coming in via Southampton as well) I've decided that since the government doesn't give a f*ck about our personal security I'd better do something about it myself. The first thing that sprang to mind was to construct an electric fence. We used to knock these up for fun in the 1960s using old Post Office relays in a make/break configuration. It was dead simple, cheap and relatively non- lethal. But that was 50 years ago and times have moved on ('elf & safety etc). So how could a fence best be implemented using current technology? One of the main drawbacks of the old relay system was that it was very inefficient, being permanently 'on' whether there were any intruders or not. I'm now thinking perhaps it would be better to use MOSFETS and a 555 timer to chop the current supply to a large inductor say 20 times a second once an earth path has been detected on the fence's live wire. How best to detect this earth path, though? Bearing in mind it would have to work in rain and shine. And how best to limit the current to non-lethal levels? All constructive suggestions welcome, cheers.