And it absorbs any energy particles in adjacent spaces (not just those that actually enter its space, as void does). You can't, for instance, fire a laser across a VIBR plate, since the VIBR will eat the PHOT and charge itself in the process. Hmm, that gives me an idea....
Another interesting one is that it constantly tries to cool itself to around 0 degrees C, and negative pressure can lower its tmp value. So you can use it as a kind of 'reverse Uranium', which will cool things at low pressure. It's not terribly efficient, but it's a novel and unusual method.