Hey, I came across this article the other day on safe-cracking and I know the howstuffworks page and matt blaze's article have been linked to many times before from the open forums, and I searched and didn't find anything mentioning this one, so I just thought I'd throw it out there; it doesn't really have much on technique (if it had more than blaze's article, I'd be really excited and also probably wouldn't post it, either) but it does have a lot of interesting history that blaze's article doesn't:
http://www.timhunkin.com/94_illegal_engineering.htm
It also has a link to an interesting page on 'safe-blowing'--apparently there were a lot of people 'back in the old days' that specifically liked explosives for safe work--again, it's almost all history, and some very interesting and detailed history at that, specifically about some well know safe-blowers like 'Scotch Jimmy'

. It's also got pictures of blown, almost-blown-but-not-quite, and completely-blown-up-because-you-used-too-much-you-idiot safes for those that enjoy that

. Here's the link to that specific page if you'd like to skip the first one:
http://www.peterman.org.uk/
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