Look Around Corners and Over Walls with a DIY Periscope

Peek over walls and look around corners with a periscope—a long tool that uses two mirrors to show you hard-to-reach places. Over at how-to site Instructables, they’ve got the step by step for putting together a periscope using a thin mints box, duct tape, two small mirrors, and an X-Acto knife. The kids will love this one.