MEGA is a cloud storage and file-sharing service with a strong focus on encrypted storage. It provides file synchronization, sharing, and communication features across devices.

Nextcloud Drive is an open-source file storage and synchronization platform that can be self-hosted. It lets users keep control of their files while providing cloud-style access and collaboration.

ownCloud is an open-source file synchronization and sharing platform that can be self-hosted. It provides cloud storage features while allowing organizations and individuals to keep their data on infrastructure they control.

Seafile is an open-source file synchronization and sharing platform designed for self-hosting. It provides efficient file syncing and collaboration while keeping storage under your control.

Sync.com is a cloud storage and collaboration service focused on privacy and secure file sharing. It provides synchronization and sharing across devices for individuals and teams.

Tresorit is a cloud storage and collaboration service built around end-to-end encryption. It provides secure file storage, sharing, and collaboration for individuals and organizations.