Learning new skills is one of the best habits you can form. It keeps your mind open and challenged, and it also provides a steady stream of accomplishment to your life. It keeps you motivated and interested in the world around you.
With this in mind, thought this list of useful sites/resources (40 in all) to learn new skills, from DIY projects around the home to technology tips and tools to make your more efficient at work, would come in handy to cultivate both personal and professional development.
Do these skills have to be particularly marketable, or even useful? There are probably many who would say that you should focus on work oriented skills to maximize the monetary value for your time. I actually see this as antagonistic to the learning oriented mindset. Of course you should learn new work skills, but that's such a basic requirement of being a successfully employed person that I don't think it counts. Plus, focusing all of your learning time on just one area of your life (your job) seems restrictive. A person who cultivates a passion for learning will find all sorts of things to explore, things that break them out of their routine (and make them interesting to talk to at parties).
And, since you never know which skills may come in useful, so why not just have some fun?