User blog comment:DragonBlade1/Hidden Blade/@comment-2150480-20100726064204

That would be appropriate considering we live in modern world, but components for that kind of a hidden blade are harder to find and assemble. I thought of building that kind of a hidden blade myself but I'm not an expert in electronics and similar stuff (yet :P). So for now I'll still be trying to do an AC/AC2 hidden blade (I'm currently stuck with the 8th concept and trying to figure out how it will work, how it should work and how to improve it - currently it's just on paper and my mind). In this concept I'm focusing on a utility-knife-like-mechanism hidden blade.