Learning outside of the workplace is, in my opinion, of the utmost importance. Whether it's reading a book, going to a convention, visiting community websites, keeping a blog, doing freelance work, or just messing around with code for the heck of it- we must sharpen our saw.
I believe the key point of this is that it must not feel like work. You shouldn't feel pressured, or dread doing something; you should do it because you want to do it. The great thing about our profession is that we can get away and do several things, all subject to our whims; if we spent all day in a chair at a desk, and we want to get up, go to a meeting like the Day of .NET (Central Ohio this Saturday!) If you like to read, do that instead; it's good to keep a bookshelf full of interesting books. Go into some kind of technical cross-training, such as learning a new language. Do design if you're a devleoper, or develop if you're a designer. Just do something.
In this way, we can continue to work on our skills, learn new things and keep from being bored. And, at least in my experience, you can bring new skills and solutions to problems you're already facing at work.