Michael Hyatt, who blogs about Intentional Leadership, has called Evernote his "digital brain."  If you don't know about Evernote yet, and you care about organizing information of any kind for any reason, you should check it out immediately.  
Regardless of your vocation or hobby, there is something that Evernote can do for you. Evernote's free version will allow you to easily experiment to find ways to increase your productivity. 
Evernote App Icon

What is Evernote?

Essentially, Evernote is a digital repository that handles all kinds of file types.  Here's a list of file types that Evernote can successfully store and/or display for you, as well as how you can get that information into Evernote:
  • Text - If it's in a text format, it'll easily fit in an Evernote "note."  You simply create a note, type in text, or copy and past text from another program, such as Microsoft Word, into Evernote.
  • Audio - You can store audio as an attachment, or even record a voice memo directly into Evernote.  Then either listen within Evernote or open the files through an external audio player such as iTunes or Windows Media Player.  
  • Video - Copy and paste a YouTube URL into a note, and Evernote will link directly to the video, or save another video file type, such as WMV to be viewed with an external player.  
  • PDF - Simply drag and drop any .pdf into a note and it will be displayed for you.
  • Images - You can copy and paste image files directly into Evernote for viewing.
  • Emails - You can forward any email to your personal Evernote account and a note will be created for you.  You can also tag the emails to be delivered to a specified folder, or send them directly to an "inbox" that you create to be sorted through later.  
  • Document/Image Capture - The Evernote App for the iPhone allows you take a photograph or capture a document image directly from the app.  It will then be saved directly to a note.  However, you can also snap a picture with your iPhone or other smartphone's built in camera and send it to Evernote via email.  
  • Web Clippings - Evernote has a browser extension (called Web Clipper) that allows you to clip and save URLs, articles, or even entire web pages into a note. This is great if you are doing research online, want to save an article for reading later, or need to keep a digital receipt from an online purchase. 
  • And More - You can place almost any file into Evernote as an attachment.  As long as the device you are using at the moment has software to process the file, you can click on the attachment within Evernote and have that file opened for you.  I have done this with Word an Excel files, but I don't think there are any restrictions here.  

Get Evernote Free

As you can see, there is almost no limit to the type of digital information you can store and organize in Evernote.  Better yet, your Evernote information is stored in the cloud, so you can access your files across all your devices (I use a laptop, iPhone, and a desktop), and even view it online from a web browser when you are away from them.  
The best feature is that Evernote is free, and allows plenty of storage space (60 MB upload limit per month) to get you started.  You can download it from the Evernote website or get it through Apple's App Store for your mobile devices. I highly recommend giving it a try. Once I started using it, I didn't look back. Start simple and see how fast your digital brain grows!