You can download your own archive of everything you have stored in Google's services. Here's how:

• Go to http://takeout.google.com/settings/takeout
• Select the products that you want to back up. I decided to select everything.
• Click 'Next' at the bottom of the page.
• Choose the file format - you can pick a .ZIP file and choose a maximum size. I recommend going with the full 50GB file to avoid having your data split into multiple files. If you choose 2GB and have a lot of information on Google, for example, you're going to have a lot of ZIP files. Choose 2GB if you're on an older computer, since ZIP files larger than 2GB require newer operating systems.
• Choose your delivery method. You can get a link via email or have the archive sent to Dropbox, Google Drive or Microsoft OneDrive.
• Tap "Create Archive."
• Be patient. Google warns the archive may take hours or days to create. It took about 20 hours for me — and I then had about 148GB of content to sort through, which is a lot.

Google will gather all of the information you've stored across its products and will send you an email with an alert including a link or notification that it's now in one of the cloud storage services mentioned above. You'll then be able to open that file to see all of your data, photos, calendar files and more.