If you need a way to organize your brain, Springpad for iPhone can help: This productivity app will never let you forget anything again. Using Springpad, users can input any sort of information they want to remember and properly categorize it (quick note, recipe, checklist, business location, a person's contact info, a barcode scan, a photo reminder, task, and more). All of the stored information shows up on your dashboard for easy access and is also automatically enhanced with useful information like directions, price comparisons and more. Springpad also syncs with users' web accounts so you can always make sure the information you don't want to forget is up-to-date.
Price: Free via iTunes