[X-Istence]

If you want a good colloborative editor get yourself some macs, and use SubEthaEdit. Realtime live editing using the standard Bonjour network. It is an awesome application, that has access permissions and other such things, it can be hosted as a general server, and then let other people access it. Then when it is saved, one can script it using Apple Script to auto check the new source code into svn, and then you can check outa copy on a windows machine with MPLab and compile it.

Also, tell SVN to just ignore certain files. With SVNTortoise you can do this easily. It will from then on not care if a file has been changed or not.