phpMAS (Multisite Authorization System) is a cross-domain PHP user-management script. Using single DB(mysql) to manage users from other sites(or domains) like YAHOO or GOOGLE, it can be integrated into many public scripts (phpBB,myBB,wordpress...)
In doing system administration for remote shell systems, I found it useful to automate certain tasks. SUMS is a collection of user administration scripts to be written solely in bash, awk, sed and C. Currently only tested in x86 NetBSD 2.0.2.