I just checked out the Mac App Store and found this little app for free today. It's called iProcrastinate and its great to say the least. It's a productivity app in the form of a simple organizer for various tasks that you have to get done. I love that it is complex, yet simple at the same time.
The leftmost column is dedicated to subjects. In my case, I have all my classes listed here. The center console is where the meat of your info is: each task. The top right section is dedicated to steps one needs to take to fulfill the particular task. Finally, in the bottom right, you will find a space to attach documents related to the task at hand.
You can color code each subject (I think of Gmail labels) and prioritize each task based on importance (Low, Medium, High). Each level of priority will then be color coded according to importance (green, yellow, red, like a traffic light). You can assign each task a due date and make a reoccurring task repeat due dates.
You can also sync your iProcrastinate to a mobile device (e.g. iPhone, iPod Touch) after you purchase the app for the mobile device for $0.99. If I had an iPhone or used my iPod more often, I would definitely get that app to sync with.
Overall, this app is totally worth the $0.00 I paid for it. I've been needing an organizer, so this was perfect!