SysAdmins: Go for it!
+ Fits easily into running systems
+ Great support from author
Much easier and much more reliable than e.g. 'amavis'
This product went in flawlessly. From nothing, to fully functional in about 4 hours, on a Solaris 8 server. Just an outstanding piece of software!
A two-factor authentication system.
A library of synchronization primitives and concurrent data structures for specific update-heavy workloads.