I make use of subversion for a good chunk of a my scripts. It's always nice to go back to a previous evision when thing go horribly wrong. Since getting subversion up and rinning I've also been putting in config files for routers, switches, and even critical stuff in /etc. Subversion is also great for hopping between platforms.  

I'm mstly stuck in a windows enviorment at work and have been using Notepad++ for editing. Otherwise vim on Linux. Most of my Linux machines are headless or console only servers, so I haven't checked out anything GUI on Linux. 

With subversion, I've found that the editor doesna.t matter much as long as it meets the basics like syntax highlighting and line numbers.