A mental affliction suffered from prolonged confinement with only limited access to stimulation; most commonly used to describe animals.
It sometimes effects people who spend most of their days in a small or crowded house. The affliction usually manifests as a strong desire to get out of the house and find mental and/or physical stimulation.
See Also: cabin fever.
It should be noted, however, that cage crazy relates more to boredom, depression, and the desire for stimulation than the claustrophobia, paranoia, and general stress that can be associated with cabin fever.
"Every day is the same: eat, work, sleep... I'm starting to go a little cage crazy; I need to get out and do something!"