Is it illegal to sell knives? Apparently in the UK it is illegal to carry a knife with a blade over 3 inches (7.5 cm) long. I saw a programme on the TV about traffic cops where they busted a van driver for having a bread knfe in his van. In the back. So he had to stop, get out and open the back to get to it. I guess they wanted to get him and could not find anything else but the case seems ridiculous to me. When I was a child (in another country), I had a pocket knife with me all the time, even in school, and no one gave it another thought. It would not even occur to anyone that someone would use it as a weapon. Different places, different customs. A WiFi cracker is a rool. It can be used for all sorts of purposes, including assessing the security of your own network. I say leave things as tey are. A DIY store cannot be responsible for a murder committed with a crewdriver or a hammer purchased there.