>That said, I'd be curious to know how long it'd take a device like this to decrypt "secure" AES256 text.

Well, according to the article it tops out at about 340 Gigahashes/second. Let's for the sake of simplicity assume it can do about 1 teraflop (10^12 operations per second, or about 2^40 operations per second). The best known attack for the full 14 round AES encryption reduces it's complexity to 2^96 instructions. So you finish this in 2^56 seconds, or about 2 billion years. I recommend you either wait for an advancement in cryptanalysis or just 30 more doublings of parallel processing power.

Passwords shouldn't be encrypted anyway. Chances are hackers will be able to obtain the key too, and then passwords are really easy to fetch.

Passwords should be hashed non-reversible (ideally using a slow hash). The original password is to no use of the application.

And sending plain-text passwords to users is even more bad[1].

[1]: http://plaintextoffenders.com/