Being able to fabricate and build your own projects is immensely useful and incredibly satisfying. While a variety of hand tools and a halfway decent vice can get you much further than many think, a true craftsman of metal needs a welder. These machines can slide and bond metals like a sewing machine does fabrics, with almost as much ease. There are innumerable applications for welding, even at this small personal scale. You might not be building an aircraft carrier or hanging iron hundreds of feet above New York, but just being able to create your own exhaust for a car is a great thing to be capable of. Having a welder opens a huge variety of options that would otherwise not be available, no matter what kind of mechanical work you do.