Version Control/Source Code Management

I imagine many readers are currently thinking that the battle over version control must surely be over by now, and that all developers are using some system. This is, unfortunately, demonstrably untrue. Let me start with an anecdote. It's 2004, and I've just started working as a systems manager in a university computing lab. My job is partly to maintain the computers in the lab, partly to teach programming and numerical computing to physics undergraduates, and partly to write software that will assist in said teaching. As part of this work, I started using version control, both for my source code and for some of the configuration files in /etc on the servers. A more experienced colleague saw me doing this and told me that I was just generating work for myself; that this wasn't necessary for the small things I was maintaining.

Move on now to 2010, and I'm working in a big scientific facility in the UK. Using software and a lot of computers...