Dropbox - Online Sync and File Sharing
Box - Box offers secure content management and collaboration for individuals, teams and businesses, enabling secure file sharing and access to your files online.
Microsoft OneDrive - Secure access, sharing & file storage
ownCloud - ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.
pCloud - Cloud storage service with up to 20GB for free! Store, share and send large files to anyone. Join now and have your files everywhere you go.
ShareFile - Secure file sharing and sync