When the blades on your circular saw, table saw or miter saw go dull, the bulk of you probably fall into one of two camps: Go to the store and buy a new one, or send it out to a sharpening service. But I know there's a subset of you that would sharpen the blades yourself, if only there were an easy way to do it.

Well, there is, if you've got an angle grinder and some plywood. While there are a bunch of DIY sawblade-sharpening jigs on YouTube, I was impressed at the simplicity of this unnamed Japanese craftsperson's design--and the fact that he also made provisions for sharpening blades that have alternatingly angled bevels on the teeth: