Have you tried out ext3? I am having fun with my backup database server pushing a high load on it and pulling the power plug on it to see it recover without skipping a beat. I have to try out JFS:Reiser.
I tried to break JFS:Reiser on Mandrake 8.1beta2 and succeeded on the second attempt. The reworked JFS:Reiser for 8.1final survived 3 attempts so I'm using that now (along with XPpro on another channel). They're both great imo but Linux's security is (of course) better since it's not shell based.