NT ssyslog (NT Secure Event Logger), WinNT, matt@dataforce.net
Price: $50+, depending on user license

This is like SRS but for WinNT.  All events are encrypted and sent to a
remote host (or multiple hosts) in real-time, to ensure you have encrypted
backups of your logs in case of a breakin or loss of data.  It will also
prevent an attacker from deleting certain events (once again, all an
attacker can do is corrupt the stored events).