We spend years on getting formal education, then get on the job training, all so that we can be very good at what we do. But once we learn towards one goal, we tend to forget all other areas of study and in the end we're experts in our areas of expertise and complete laymen in others. There is nothing wrong with that kind of scenario, except we're limiting ourselves both professionally and personally by not being able to do much more than what we're paid to do at the moment. To open up our horizons we should step outside the box and start learning different skills.
One area is things you can learn to improve your value as a worker in the specific industry you're in right now. If you're working for a web design company, think of expertise in medical practice or law firm web design; if you're a kindergarten teacher, learn to play the piano or to work with speech impaired kids; if you're a chef, sign up for courses in baking or wine making. Learning new things strictly connected to your present job will put you ahead of your coworkers and also give you the upper hand should you decide to look for work elsewhere.
If you're not convinced your career choice is right, you should consider learning things that would help you in transition to a different job. First think of what jobs you find interesting and where you would like to be in a year or five career-wise, and then start learning the skills necessary to make it happen, whether it's sound mixing, driving a semi-truck or systems analysis. Since it's never too late for a career change, it's never too late to learn skills necessary in a different job.
Work is one thing, and your private life is another. There are plenty of things that you rely on others for that you could do yourself if you only knew how. Doing those things yourself would not only save you up some money, but also give you the pleasure of completing a task with your own hands and incentive to take on more projects or to learn yet another skill. For example, learning to shorten new pants or to replace a broken zipper may give you the confidence to try and sew a skirt and that may lead you to taking a sewing curse so in no time you'll be creating and fixing clothing, window treatments and stuffed animals for the whole family.
Any skill, big or small, is worth learning, because you never know when it might be useful to fillet a fish or to fix a car. Life, both professional and personal, is full of unpredictability, so the more you know, the more you're prepared for what's ahead, and you'll be able to react and act. Sometimes it may save somebody's life, like if you know how to perform a Heimlich Maneuver, other times it may save the day, if you know how to fix the bride's ripped dress, that's why instead of sitting in front of TV all day long, you'd better grab a how-to book and learn to do something because you never know when you may have to know it.