Whether you’re trying to catch an intruder or give someone a good scare, you can build this simple tripwire alarm in only a few minutes. This post is part of our Evil Week series at Lifehacker, where ...

Instructables user [EngineeringShock] has been hard at work building a laser trip wire security system, complete with a combination lock. The security system works just like you see in the movies, ...

Sometimes security doesn’t need to be overly complex to be effective. Instructables user [1234itouch] recently built a simple laser tripwire alarm that can be mounted virtually anywhere, complete with ...

If you ever feel the need to make your own salvaged part trip wire alarm, it turns out it’s a pretty easy process. Over on YouTube, Node walks you through it. All you’ll need is a piezo buzzer, a ...