[CentOS] Hardened ver of CentOS?

NSA guides on hardening RHEL5. Should be applicable to CentOS5 as well.
http://www.nsa.gov/snac/downloads_redhat.cfm?MenuID=scg10.3.1.1

I read about this on /. some weeks ago, but I just skimmed through it,
so I can't say how effective I think it is. I thought it would be
useful to point to it on list though.

HTH,
Filipe