You should write things down...

According to a new study, the average person would save about 90 WASTED MINUTES every day if they organized themselves better with a to-do list. That adds up to an extra 23 days a year, which is enough time to watch 328 movies, eat 547 extra meals, or have sex at least 1,095 times.  But that's not how you'd spend the time. Most people say they'd use it on housework or chores.

Or maybe you shouldn't... This is from the Harvard Business Review:

Stop making to-do lists. They're simply setting you up for failure and frustration. Consider the to-do lists you're currently managing: how many items have been languishing since Michelle Bachman was leading the field for the Republican nomination? How often do you scan your list just so that you can pick off the ones you can finish in two minutes? How many items aren't really to-dos at all, but rather serious projects that require significant planning?