BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
Mega - Secure File Storage and collaboration
Userscloud - Userscloud is a free cloud service that offers unlimited online storage, remote backup capacity, fast uploading, and downloading tools.
Cloudfogger - Easy and secure encryption for the cloud. Provides security for all cloud storage services like Dropbox, OneDrive and Google Drive.
Subyshare - Subyshare.
Google Drive - Access and sync your files anywhere