It is always a bit difficult to actually think about doing backups. Either you spend too much time thinking about it or you forget about it. For Windows, I found a nice free utility program: FileHamster from MOGware.
This small utility will allow you to automatically backup every single file you save or modify. FileHamster will create a full history track of your activity without even the need to think about it. It acts immediately (you don’t have to wait for a daily backup), and keeps everything. Of course, you need some free disk space, but it’s so much of a relief…