As computing power has increased, the available horsepower to
brute force crack RSA algorithms has grown as well. The most
recent announcement, in December 2009, was that a group of
mathematicians, computer scientists and cryptographers had
managed to factorise a 768-bit RSA key using a technique called
the number field sieve or NFS. That puts the next milestone, the
1024-bit RSA key, in reach in the next decade or so.
More here.
