Add extra privacy to your Google Files
You can easily use Syncdocs to sync your Google Docs to and from your PC. Syncdocs and Google Docs are both secure.
However, if you share a Google account with others, and want to keep your own cloud data private, take a look at Secret Sync. It encrypts all you data locally so that your data is completely private, accessible only to you on your local PC. Syncdocs still syncs all your data to Google Docs, but the chosen Secret Sync folders are encrypted on Google Docs and Apps.