Test the latest Blobfish Signer release by yourself at http://demo.blobfish.pe/blobfish-signer-webapp/.

Download John_Doe_test_certificate.pfx (password is secret) if you need a digital certificate for testing. Additionally, if you need the corresponding root certification authority (e.g. to install it as a Trusted Certificate in Adobe Acrobat) you can extract it from the previous PFX, for example, by exporting it from the certificate store after importing the PFX.