Gretchen Rubin wrote The Happiness Project, a book that I have heard about from a few people, and that I plan to read. Her book was born out of her blog which recorded her year of personal research about happiness.
I will write more about the book, her blog and other things later, but here's her blog The Happiness Project, if you're interested. She has some great ideas and articles.
She also has two nice, short movies she's created, they're nice reminders about how we choose to spend our time... Here are their links:
"The Days are Long, But the Years are Short"
"The Secrets of Adulthood."