Dropbox - Online Sync and File Sharing
Cloudfogger - Easy and secure encryption for the cloud. Provides security for all cloud storage services like Dropbox, OneDrive and Google Drive.
Google Drive - Access and sync your files anywhere
BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
Microsoft OneDrive - Secure access, sharing & file storage
Mega - Secure File Storage and collaboration