Not sure if you've tried this or if it's practical for you, but I've found that having a completely dedicated space, with dedicated tools, can create a working context that helps boost productivity. I won't name them due to privacy concerns but my company has been very good about dealing with remote workers and provides a basic set of office amenities to any worker who is selected to go remote (convertible standup desk, remote access point with office telephone, all-in-one printer w/ ink refills, etc.)
> Over the years, I can't even count the number of times that I heard a conversation taking place and was able to step in and say "that's wrong" and stop several people from a multiple day detour.
I'm not sure what your experience is but a trend I've noticed is that this tends to occur when only a subset of team members are remote - in fully-remote teams the use of collaboration tools (mailing lists, Jabber, IRC, etc) can often replicate these kinds of ad-hoc conversations with the added bonus of automatically capturing the information discussed.
I generally think environments where ad-hoc conversations are necessary to maintain overall effectiveness as being tool deficient.