Ranked in these QuestionsQuestion Ranking
Pro Free and open source
StackExchange Blackbox is free and open source. It's released under the MIT license and its source code is freely available on GitHub.
Pro Uses a VCS repo to store the secrets
SE Blackbox works with Git, Mercurial, Subversion and Perforce to store encrypted secrets file in a repository. Files are automatically encrypted and decrypted using GNU Privacy Guard.
Pro Easily share secrets with other team members
Since the secrets file is stored in the remote VCS server, anyone that has access to it (team members) also have access to the secrets file.