Second attempt... I was disturbed by the lack of an obvious way for it to open :-)
It was worth going through this as I've learnt more about the mirroring modifier - particularly how it works with the object origin.
I've also realised that I didn't need to apply the mirror modifier to the box so that I could have the hinge and lock flap different on the front and back; I just needed to have two different objects with their own different mirror modifier.
Haven't had much time since Monday, so here's my work in progress for the disk drive... hopefully I'll have some time tomorrow night to finish this off and get more done.
I thought I'd add the power button to the back. Learned a few things in the process. I wanted to apply the hole booleans as my machine was struggling. I realised that applying the bools with the mirror in place on the body mirrored the holes to the back, so I ended up applying the mirror first, then applying the front bools to get the holes on the front and not the back. I separated the side hole bools and mirrored them to get both sides, then applied them to the body to get the holes on both sides.
I'm interested to know whether this was a good way to do it or whether there was a better way.
Here's a render of the back with the power button - I want to move on to the subsurface stuff, so won't bother with the other sockets on the back.
First cut of my low poly room - blocked out my home office (if only it was actually that tidy!)