I mostly compose directly in software. One of the things I find is hard during the composition process is pressing the delete key when something isn't working quite right. I don't want to lose some fragment that I might want later on, but on the other hand, I don't want to keep it around cluttering up the score at the moment either.
As a software developer, at work we use a "version control" system to keep track of changing source files. I was wondering if anyone who composes in a notation program has tried using a similar system to keep track of revisions to a work-in-progress. I'm considering trying it out myself. (For any other programmers, I'm thinking of a tool like subversion or git. I'm not sure how diffs would work, though)