Welcome to the Reiser4 Wiki, the Wiki for users and developers of the ReiserFS and Reiser4 filesystems.
For now, most of the documentation is just a snapshot of the old Namesys site (archive.org, 2007-09-29).
There was also a Reiser4 Wiki (archive.org, 2007-07-06) once on pub.namesys.com.
Reiser4 patchsets
From Reiser4 FS Wiki
stable patchsets
As reiser4 is still not in mainline, Edward Shishkin is kind enough to provide patches for the stable version of the Linux kernel.
development patchsets
Andrew Morton is maintaining the MMOTM tree (mm-of-the-moment) that includes Reiser4 as well. Snapshot patches from that tree can be found on kernel.org. Be aware that this tree in high flux and often filled with exotic stuff (yes, more exotic than reiser4 ;-))
After applying the patches please test and report any issues!