Yes. And I think that has been suggested several times in several threads suffering to the bitcoinia scam. Stephen Gornick probably knows where they all are.
With regards to oauth here is an interesting read.
https://bitcointalksearch.org/topic/m.1058906
On of the interesting things of the MintChip Challenge was that each hosted MintChip was assigned a unique SSL client-authentication certificate and a key, signed by the Canadian Mint and distributed in the form of password-protected PKCS-12 files (.p12). These credentials then had to be installed on the client device prior to accessing any of the hosted services. I know there is a raging debate about reliability and security of SSL certs due to the microsoft and other compromises, however I found this an interesting and potential solution to the bitcoin security problem.