We had similar problems last year with crazy filenames and no way to tell which was the latest or not. This year I set up a CVS (version control) system and all of us writing software are much happier.
For those who don't know what version control is: version control allows you to save multiple versions of a file (using the
same file name) on a server. This allows you to go back to an older version at any point. It allows you to look at what changes were made, and when. You can also give a "tag" to certain versions of a file when that version represents something important. For instance, we tag all of our files any time we use those versions of that file to compete, any time we reach a major milestone, etc.
I'm not explaining this very well. If you're interested, try reading the Overview for CVS:
http://www.cvshome.org/docs/manual/cvs_1.html#SEC1 CVS is free, by the way.
Setting something like this up isn't all that hard, but it's not trivial either. However I highly recommend it to any team. It's made our lives so much easier.
As a side note, version control systems like this are used all the time in software engineering, so if you're thinking about going into that field it would be very beneficial to you to know something about it.