A slightly older version of ripem can also be found on rsa.com, with much less complicated access (you read a readme file which tells you the rules, and tells you to cd to a random-named directory); you don't need to get an account there or sign anything. It's also got RSAREF, of course, and does have the latest version of that. I assume they'll get current RIPEM there soon, and maybe RIPEM-SIG.