Should it be on the development servers or a Subversion server?
I suppose this could be expanded to any client-server version control system.
We use a clean, blank slate for our repositories. Specifically, we use Slicehost for our main repository.
We started with a 256MB slice and upgraded later on to 512MB. Slicehost is great because you know you have a completely clean server to start with, and can build the things you need on your own.
Slicehosts' articles are top-notch.
Our repo server looks like this:
And that's about it. Not much overhead.
Edit: Not trying to sell Slicehost here, so if that's not kosher, let me know!
Edit again: James makes an excellent point about hosting proprietary code on a third-party server. Extra care should certainly be taken when selecting a host to do such a thing. Unfortunately, many companies simply don't have the resources to build and manage servers in house, which is where we found ourselves prior to selecting a host for our code.