I've been wondering about the feasibility of using SPKI certs. I quite like some of the features (delegation) and relative ease of implementation (compared to X.509 certs)...of course, readability of certs could go a long way to helping end-users evaluate for themselves the trustworthiness of the cert. While pgp certs could probably be a good alternative (given the existing user base and infrastructure)....even though lacking in the ability to delegate. However, I'm a little wary since at the moment there seem to be just a few sources of info or proponents (even though their arguments seem convincing to me) when it comes to SPKI. I am also not aware of any products or PKIs that use SPKI certs. I would really appreciate if someone could refer me to instances of actual usage of SPKI certs.