Here (courtesy of Mike Zorn) is an article in the trade magazine, InfoWorld:

It’s

about the Japanese quantum computer project. Computers faster than greased

lightning would be nifty in cryptography, because the most popular modern

cryptographic methods are based on the fact that while multiplying two

humongous numbers together is easy, the reverse thing–factorizing a huge

product into its component primes–is tremendously time-consuming. Well,

about halfway down the page , where they’re talking about how fast a quantum

computer is

and what might be done, there’s this:

“That means calculations, such as working out the factors of prime numbers,

which present problems for even the fastest supercomputers could be

trivialized by a quantum computer.”

I could tell them THOSE factors for free, and real fast….