Well, it does have a couple of relays and a small control transformer in it (all seem to be connected to that D-sub labeled "pod", but I don't see the unit as having any intrinsic collectable value. If you don't have the control "pod", it's pretty much useless.
DEC PDUs have a connector for daisy chaining several PDUs so that you could turn on several cabinets with one button. I'm guessing the "POD" connector here does the same.
Keep or toss? Well, someone who has a systime system would probably want this.. for anyone else it is just rather bulky and useless.