[QUOTE="Dr Zoidberg"] I just got a BFO chain from a DIY shop and concreted the middle of that into the ground where I was planning on laying my patio , with the two ends of the chain loose. They then came up between a couple of the newly laid slabs and could be padlocked through a wheel/bit of frame on a bike that was ridden onto the slabs. A BFO petrol powered angle grinder would have got through it without too much difficulty I'm sure , but that would have been pretty conspicuous and not something a casual thief would have had with him.[/QUOTE] You've never seen that video of a bloke walking up to a bike in the middle of New York and angle grinding the lock off whilst everyone just walks past, have you?