Related Clues:

• Computer critter
• Sewer resident
• Common test subject
• Muppet Rizzo, e.g.
• Plague carrier
• Dirty dog
• Nocturnal rodent
• Untrustworthy one
• Timid creature
• Lab maze runner
• Computer item with a tracking ball
• Untrustworthy sort
• It may be down in the dumps
• Timid one
• It makes a clicking noise