https://www.vaultproject.io and so should you
Right now, I'm encrypting sensitive values in Consul for expediency. I'm going to implement Vault with an AWS back end eventually.
I think Vault can be great for teams that are sufficiently large and sophisticated on the DevOps front. I felt there was a need for more of a Heroku/1Password-style tool for teams that want a secure way to manage secrets without undertaking a big project to setup/maintain their own secrets server.