Thales SafeNet Luna HSM - Thales SafeNet Luna HSM is an open-source HSM that protects encryption keys used by applications in on-premises, virtual, and cloud environments.
AWS CloudHSM - Data Security
Yubico YubiHSM - YubiHSM is cryptographic protection for servers, applications, and computing devices.
Amazon Key Management Service - Sysadmin
Unbound Key Control - Unbound Key Control is a software suite that provides visibility, control, and audit of secrets across hybrid multi-cloud environments.
Azure Dedicated HSM - Azure Dedicated HSM allows you to create and maintain keys that access and encrypt your cloud resources, apps, and solutions such as Windows Azure SQL Database.