As with everything that has been said here -> introduce source control.
If I had a penny for every time that I've read about (or heard from friend's about personal) projects that have either had to be scrapped or started over because they didn't have source control... you know the rest.
Seriously, you/your company might feel like you don't need source control right now, but as when (and I hope this doesn't happen) someone deletes the wrong file, or makes a mistake, or bit-rot takes a crucial file you'll know why we use source control.
If it's a problem with management (as in they don't want to fork out for it), then inform them that there are free solutions. If they don't want a free solution, do a cost analysis of how much money it would cost to start a given project (or all of them) from scratch vs how much a licence will cost them.
If it isn't a management decision, then get on to who ever makes that decision and inform them that they should be considering source control.
I even use source control in my personal projects. One of my big projects was destroyed due to bit-rot, and once was enough to convince me that I needed some form of remote source control (for the record, I use GitHub for me personal stuff and we use Team Cohesion where I work)
EDIT: I came across a related video, just now. It's about how Pixar nearly lost the entirety of Toy Story 2 when someone keyed in the wrong command - http://www.tested.com/videos/44220-how-pixar-almost-lost-toy-story-2-to-a-bad-backup/