decrypting many files to stdout

[Ken Takusagawa]

I have many files that are all encrypted with the same public key, and
the private key is protected with a passphrase.  Is there a way that I
can decrypt all of them at once, concatenate the results and print it
all to standard output but only have to type my passphrase once?  I'd
like to avoid having the decrypted files be written to disk, i.e., I'd
like "-d" behavior but with multiple files.

--ken