as far as "heavy duty chains, padlocks and cables" go, i've got some 4' bolt cutters that will cut through just about any padlock or chain you could carry (them giant boat anchor chains might give me a problem) like butter. i used them when i worked climbing towers, and a lot of sites have daisy chains made out of padlocks on forestry gates, basically like 20 locks locked together for all the various companies, and every now and then someone would skip your lock and lock you out, so we'd cut them. i've cut through the best locks ever made without breaking a sweat, or putting a dent in my cutters. i've cut through 1/2" steel rod with them, so they'd probably cut right through your average bike rack. i also had battery powered band saws and sawzalls, too. what i'm getting at, is if someone wants your bike that bad, they'll take it. even if you disable the bike so you can't ride it, they could just throw it in the back of a truck. i just have a U-lock, but what really gives me of mind is, my bike is unique. there's not a part on it that i wouldn't recognize, or a few thousand forum members wouldn't recognize, it's legally registered with the DMV so it's in a nation wide database, so if anyone takes it, they better just keep it in their house and never show it to anyone.