Calamarain
The Calamarain are intelligent, non-corporeal lifeforms that exist as clouds of ionized gas. They were once tormented by Q, who insisted that he did nothing "bizarre" or "grotesque" to them. The Calamarain communicate with high-pitched noises and grindings. They emit Berthold Rays when probing something.
When Q lost his powers in 2366 and was exiled to the USS Enterprise-D to live as a human, the Calamarain sensed the chance for revenge and attacked Q and the Enterprise. To save the ship, Q took a shuttle to divert the Calamarain's attention away; this noble deed convinced the Q Continuum to restore his powers. Q immediately attempted to exact retribution against the Calamarain, but Q2 forced Q to let the Calamarain go without harm. (TNG: "Deja Q")
