I'm obsessed with these two blogs. I found them in Technorati's list of the top 100 blogs.
Lifehacker - Tech tricks, tips, and downloads for getting things done.
Zen Habits - Zen Habits is about... achieving goals, productivity, being organized, GTD, motivation, eliminating debt, saving, getting a flat stomach, eating healthy, simplifying, living frugal, parenting, happiness, and successfully implementing good habits.
(Scroll down to the bottom of the Zen Habits page to see a list of the most popular posts.)
Check them out!