Google Drive (this link opens in a new window) is a wonderful tool. However, it lacks encrypting. So this limits its use somewhat. I use a file zipper to encrypt to add another layer of security for my personal data files that I store on GDrive. Here's the process I follow:
1) Use 7-zip (this link opens in a new window) to create a zip file of my file, files, folders, etc. I chose the AES-256 (this link opens in a new window) encryption and enter a password.
2) Next upload the file to your GDrive
Whenever I access the file from any computer I open with 7-Zip. It
requests that a password be entered and then the file (or files) can be
extracted. I almost always use the "Extract inside" selection. This way,
when I modify the file and save it it will automatically be updated in
the zip archive. That's a timesaver and a good reason to use 7-Zip.
I have 7-Zip installed on all of the computers that I might want to view the encrypted data.
You don't have to use 7-Zip, there are other zip routines which have encryption capabilities.
This system works well for me and protects my sensitive data.