Hmm, so in relation to this thread, I was just at Staples (office supply chain on this side of the planet), and found sets of 6 stacking 'letter' trays, clear or black, for something like $7.
The interesting thing is that they're designed perfectly for a number of off-label uses. Open on the wide side, vented on the sides (all the way 'down' to the tray), and with an inch-high notch across the width of the back that suddenly becomes a cable slot if inverted.
Inner dimensions are: 8.75" 'deep,' 12.5" wide, 2.25" high; the tray/shelf has a similar notch in the front that takes it back to 7.5" 'deep' across most of the width.
...
Upside-down, you end up with a set of 'shelves' that could easily hold a stack of hubs or other lightweight equipment... like the Magnavox tuner I use with my old 1802. You also gain a 'free' shelf that way, for not having one tray at desk level... and used individually, they could serve as dust covers/space-savers for small hardware; just push one back over the wires when you need to access the keyboard.
Downside is that I just looked up the specs on the 600, and according to emugaming, it's "14" deep x 9.5" wide x 3 high." ... So maybe these aren't going to work, but legal-sized trays might.
