I just finished creating two Addons for the ReadyNAS Duo, NV, NV+, 1100 and X6 that allow you to host SVN repositories. The first obviously is Subversion itself. This addon includes all the subversion command line tools and also adds support for accessing the repositories on your ReadyNAS through the browser interface.
The second addon is WebSVN. In addition to browsing the repositories in a much nicer interface than SVN itself provides, this modified version also allows the creation of new repositories for authenticated users. To use WebSVN, PHP support has to be installed on the ReadyNAS which can be achieved by using the PHP_1.1.bin from Readynas.com.
As always: Works for me, ymmv. If these addons break your ReadyNAS you own the parts.
Ah, and before you ask: Yes, versions for the Intel based ReadyNAS products are to come shortly. Don’t hold your breath, though.