Considering that man's first contact with an alien intelligence was with the Non Biological Entities (which technically occurred in prehistory) humans were incredibly optimistic about encountering alien life. Optimism in this case is defined as short sighted. We were looking for aliens like us though with weird hair and skin tones or funny shaped head. Essentially like us in the gross particulars. They ate, drank, respirated, poo'ed. All that good stuff.
The optimism was short lived.
Humans continued to encounter more and more different types of NBEs, the familiar huants, overt and poltergeists as well as types that seemed to defy classification. These are called sorcerers after Old Earth legends. Sorcerers seem to laugh at most capture systems. They are similar to poltergeists in feeding on psionic energy. In the case of a sorcerer they feed on psionic energy exclusively with deadly effects to unshielded minds. They are also far colder than the lesser NBEs appearing as cool areas to infra red scanners. A sorcerer can cause hypothermia in a human.
The most frightening ability of a sorcerer is its power to control other NBEs. Some sorcerers have killed a ship's psionic or driven them mad and then freed the NBEs leading them on a rampage that usually ends with the destruct button being pushed. This actually destroys the drives preventing further movement by the ship. The crew compartment can usually survive this but they usually have stocks of cyanide. If things are really bad the captain is supposed to hit the kill switch to prevent his ship from becoming a lure for other spacers. Not all captains push the button soon enough.
Special Ghost Lights automatically snap on when the destruct switch s thrown advertising to all that the NBEs are in charge of the ship. Any rescue efforts by other parties after this are purely optional. Some mad and greedy individuals will mount salvage operations on a ghost lit ship. Few crews will every want to fly in such a ship. Patrols will usually tow these hulks to the nearest gas giant or ice moon and drop them there to chill the NBEs into hibernation. Sadly sorcerers seem to resist even this for months, maybe years.
Some cultures worship and adore NBEs however, giving their ghosts free run of their ships. The entities are usually commanded by a sorcerer who has shown the ability to work with its human worshippers. These slave ships have large crews to feed their masters and are usually not allowed into most starports.
Another frightening ability of the sorcerers is their control of machinery. In Ghoul cultures they are frequently supplied with robot shells of ornate and sepulchral design to better make their wishes known. it is unknown how much of the robot's demands are the result of the NBEs it harbors and how much is the result of the programmers, to further oppress their living citizens for humans operating behind the scenes. Communication with such robots follows that of most NBEs: disjointed, obsessive at times and explosive without warning.
What is worse is the use of living humans as vessels for NBEs. Possession of a human is a feat only the most powerful NBEs can manage on their own. Ghouls and other cults advocating NBE supremacy use drugs, implants and torture to break down human resolve and allow the entities to move in. Again demands and behavior is disjointed and erratic, often masochistic as though the rider indulges in all many of sensations humans would find unpleasant. Possessed humans are hard to detect other than by mental probing. the possibility of innocent tourists being NBE sleeper agents is something the Empire has nightmares over (hence the lengthy quarantine before being allowed to land.
Coronans are a life form that may be related to the NBEs. They are creatures of plasma and energy that develop on stars and in the hot Jupiters that surround them. They appear as balls of light. They are not capable of the telekinetic effects NBEs are. However they will sometimes pay for passage to a new system by riding in your fusion generator and amping it up a bit.
Coronans are friendly and hospitable creatures. This might be because they want almost nothing humans can give them. A little metal vapor, a few megawatts of sunlight and they're good. They too produce oddly disjointed conversations with humans, however their observations are less creepy. Electronic weapons such as capture fields will work on them to a degree but they can usually burn their way out of most containment facilities using some of the plasma that makes up their bodies.
Humans that make extensive use of fusion drives such as the Dynastics often hire Coronans to monitor their engines from the inside in exchange for power and some ionizates. They're part engineer and part engine.
NBEs and Coronans hate each other and will attack each other on sight. In such contests the advantage is the Coronan's as even a young spark of a Coronan has enough heat energy to roast most NBEs. A Sorcerer capturing a Coronan is something no one wants to think of. While they may be related humans have learned it's a good idea not to point out any similarities between NBEs and Coronans to either party.