I was pointed at an interesting paper on email and non-verbal communication [PDF] which tries to explain, through some experiments, why people can't communicate as well as they expect to be able to over email and other non-verbal communication methods.

It's an interesting paper though it sort of scares me given that I work from home and basically only interact with my colleagues and friends over IRC, email and occasional phone calls. I'm sure I've seen things go awry due to the sorts of miscommunication that only seems to happen when you don't actually speak to someone. I'll have to try to ring people more.