I finally got Subversion set up over SSL hosted by Apache side by side with IIS.  The biggest problem was getting IIS to let go of port 443.  I'm running XP Pro SP2 and I'm not hosting any SSL from IIS, but it would still bind to port 443.  I found lots of information on configuring HTTP.SYS using httpcfg.exe (There's lots of other very cool SP2 tools in the download), which I though was really cool, but nothing that kept it from binding to 443.

My rather rudimentary solution was to start Apache first.  IIS/HTTP.SYS didn't complain about the port already being bound to.  It works like a charm now.  Now I can get to my repository from work through the firewall!  What I don't know is if the sequence of events at boot time will keep it from working right.  Any ideas?

I'm wondering how hard it would be to write a Subversion server on HTTP.SYS.  Now THAT would be cool!  I think it would only be a matter of implementing (or finding an implementation of) WebDAV and hooking into the Subversion API.