Using different filesystems

There is a semi-hidden option in the installer that allows you to pick non-jfs filesystems during installation: At the initial bootup prompt of the installation CD (where you'd also specify vga16 or acpi=off), use

fs=Filesystem

Possible values for Filesystem are, as of 2006.1: ext3, jfs, xfs, reiserfs

For a performance comparison, take a look at the Filesystems page.