If you're really, really anal about cutting things in a straight line, have trouble keeping your hands steady when you aren't drunk, or have Parkinson's, this tool is for you. It's a laser-guided hand saw, and it tells you exactly where to cut to make sure that line is as straight as possible.
I mean, just imagine what kinds of problems you can avoid by always cutting in straight lines! Problems like, uh, crookedly cut pieces of wood. And, well, other cutting-related mishaps, I'm sure. Whatever, I'm no carpenter. If you think this is a good idea, go buy one. What am I, your dad? Leave me alone already.