I don't tend to think it's that dangerous, but it's certainly messy. Another couple hours of work could have had proper mounting with nicely routed cables, doors that close and status indicators. It still wouldn't be super safe, but it would look much cooler.
And really if you're jamming servers in a file cabinet you're probably going for looks, not fault tolerance.
It holds backup storage and runs a testing server - not very often. Since first posting the blog, it's been re-positioned/turned 90 deg. with drawers now facing to the window. A good fan blows from the back (through some vents I cut out; blows air up and out window) while it's running. It works.
Isn't this a fire hazard? Aren't you afraid of damaging the components? Or getting electrocuted?