This blog is focused on the art and science of software development, but I don't want to imply that the contents herein represent a full picture of a programmers life. A great deal of outside experience ultimately influences your qualities as a software developer. This varies by person and personality, but for me the key outside activities for success are reading and walking.
The best source of inspirational reading in our rapidly changing world is a good library. Here you'll discover various trade and technical magazines, and the library may subscribe to online services that you wouldn't otherwise consider visiting. You should make an effort to research the state-of-the-art in the business use of computers as well as strategic advancements happening in your industry and related industries. I also recommend a broad general reading background of a variety of magazines: you never know when a strange juxtaposition of unrelated ideas will lead to a new breakthrough.
I can't overstate the value of walking. Not only does it clear your head of the clutter and confusions of political interests, the rhythm of your legs and the change of natural scenery will make you more aware of the proper balances in design. It will help you create a more naturalistic and organic path for your growth. Walk. Read.