The shred command and security?

[Mike C]

In the event that you want to give a Fedora machine to a friend but want to
remove sensitive files first, an obvious tool is the shred command.

However the man page for shred says:

"CAUTION:  Note  that  shred relies on a very important assumption: that the
file system overwrites data in place.  This is the traditional way to do
things,  but  many  modern file system designs do not satisfy this assumption.
The following are examples of file systems on which shred is not effective, 
or is not guaranteed to be  effective  in  all file system modes:

* log-structured or journaled file systems, such as those supplied with AIX
and Solaris (and JFS, ReiserFS, XFS, Ext3, etc.)"

But further down it also says:
 
"In  the  case  of ext3 file systems, the above disclaimer applies (and shred
is thus of limited effectiveness) only in data=journal mode, which journals
file data in  addition to  just  metadata.  In both the data=ordered (default)
and data=writeback modes, shred works as usual."

So I presume that if you have a default system using ext3 then the shred command
does give safe deletion?

Are there any other commands that will securely delete files/directories?