It is so wonderful to work simply for the joy of it! Keeps you coming back every day. Even when the sales and the acclaim are not there, you have your unique experience of joy. Exploring the beauty of something that isn't readily apparent to you can be an experience that is deepening. We learn from watching others: what we like and don't like, what processes might be applied in our world, changing our working pace, (taking more time for some, less thinking and more doing for others, maybe being mindful with every new phase of our project), drinking in the ordinary, breathing in deeply what we are experiencing, no matter how banal or mundane.
Listen to music of people different from yourself - Generationally, culturally, geographically. Music is the reflection a generation, a country, a lifestyle, an individual. If you are in the corporate sector explore the world of street artists - look for risk/risk adversity, organization, methodology. If you are a fine artist, learn more about performance art or better yet, allow a child to share his creative experience. If you sing rock and roll, listen to Mozart, Beethoven, Bartok, Bernstein. If you work in sales delve into the art of merchandising, read biographies of entrepreneurs and note how they got the word out; Writers learn much just from listening to the stories of others.
You can be renewed in your own enthusiasm through the naive or cynical views of someone else. Strive for difference. Value familiarity. Finding joy in your work, no matter what that might be, is the not-so-secret-to-happiness in the workplace!