Roy Osherove is asking about collaboration support in text editors to enable remote pair programming. I honestly don't know anything about what editors support something like that, though definitely seems like a feature worth checking out.

However, we've used in the past the Remote Assistance features in Windows XP and up very successfully to work remotely. It's not perfect, but that coupled with Instant Messaging seems to make it a lot easier.

Pair Programming, Remote Assistance