RSA-160 is factored!
Researchers at the Bundesamt für Sicherheit in der Informationstechnik (BSI) in Germany recently completed the factorization of RSA-160, one of the numbers from the original RSA Factoring Challenge. The sieving effort for this 530-bit integer involved about twice as many relations as for RSA-155, but took less time and required fewer machines, presumably due to hardware advances over the three years between the efforts, though MIPS-years estimates have not been given. The resulting matrix was somewhat smaller and easier to solve due to better algorithm choices. Please see Paul Zimmermann's factoring page or the BSI Newsletter (in German) for more information.