One of my coworkers at Cheezburger asked me to post pics of my GTD, Getting Things Done, system. I put my to do's up on the wall next to my desk. I'm a visual person, so having tasks on paper where I can see it at all times is a winner. I've used digital task management tools such as hiveminder.com and teuxdeux.com but I do best with paper systems.
Each task is written up as the next actionable task. There's a row for things to do today, a row for tomorrow, this week, and this month. I change marker colors each week so I can tell what tasks are really old.
Once the task is completed, it goes to live on the World of Stuff That's Done. It's very rewarding to move post-its to the completed wall.
I've added an Awaiting row at the top. Tasks are docked in this row if I'm waiting on something from someone else. It's been very helpful in my morning standups in answering the "what's blocking you" question.