XFS download mirrors:

SGI-released packages and patches

oss.sgi.com also has an rsync server:
rsync://oss.sgi.com/xfsftp/

Since release 1.0, most files are also mirrored on SourceForge:
ftp://xfs.sourceforge.net/pub/xfs/

Jan H. Schrewe's mirror in Germany:
ftp://ftp.mpg.goe.ni.schule.de/pub/linux/kernel/xfs/sgi

Denmark mirror:
ftp://sunsite.dk/mirrors/xfs/

Netherlands mirror:
http://mirror.math.leidenuniv.nl/oss.sgi.com/

Full install mirrors:
ftp://ftp.thebarn.com/SGI/

Australian mirror:
http://planetmirror.com/pub/sgi-oss/xfs/
ftp://planetmirror.com/pub/sgi-oss/xfs/

Contributed Packages

Mark Pinto has kindly provided Debian packages:
http://www.markybob.com/xfsboot/

XFS patches are also available in Debian-unstable ("Sid")

Chmouel Boudjnah has provided Mandrake packages:
ftp://ftp.sunet.se/pub/Linux/distributions/mandrake-devel/contrib/RPMS/