[TriLUG] OT: cryptography challenge

[Owen Berry]

Given the following 4 encrypted/obfuscated strings, have a wild guess
what the encryption algorithm/method is.

x86IMZ+WprrGD5I2Tjdm6w==
86oVwKg2TgWoAxaeOTe98A==
4LxtpStocPwNFUvuJBhgEw==
R5nGoWiwxkJafQLgcey4GA==

The first 8 digits of the current time in seconds since 1970
(date +"%s") is part of the encryption/obfuscation key.

The above strings are passed as part of an HTTP get and therefore may
have been encoded in some manner after encryption/obfuscation. Any
guesses on what this is if you don't have a guess on the encryption
scheme?

The format looks very familiar to me, but I can't remember where I've
seen it before.

Note that this is not for anything illegal.

Owen