SLAC has recently started supporting ssh2 with kerberos5 ticket forwarding to allow access to AFS on SLAC unix. After some experimenting I have found that the following tools work very well together to provide convenient access to SLAC unix from windows. Using these tools it is possible to sign on once using MIT kerberos with your unix username/password and use that token for access to AFS, ssh, cvs and scp.
Tools
OpenAFS
MIT NetIdMgr (1.3.0.0)
Available as part of http://web.mit.edu/kerberos/dist/index.html#kfw-3.2
PuTTy (0.58 with GSSAPI extensions)
There are many versions of putty which claim to have GSS extensions, but the only one I had success with is this one: http://www.sweb.cz/v_t_m/putty/PuTTY-0.58-GSSAPI-2005-07-24.zip