I recently began putting just about everything, especially at work, into a revision control repository.  I find that I feel much more comfortable toying with changes in a presentation or document if I know I can easily get the previous version of it.  I noticed Martin Fowler seems to be headed in the same direction and has come to the same conclusions I have about revision control support in applications.  For instance, right now it's very difficult to tell the difference between two version of a presentation.

I noticed the latest version of FxCop has an option to save the file in a format that is friendly for version control.  Perhaps the new XML-based office formats will give us similar capability?

[Update 12:35] I forgot to mention Subversion, without which, the above would be very painful.  I'd also be interested in other people's revision control story.  How much has it seeped into your computing life beyond coding?