Findings:

• Titus Groan
• Groan
• Grumble
• grumble and grunt
• Grumbles from the Grave
• Grumble (user)
• SA-10 Grumble
• grumbles (user)
• SA-N-6 Grumble

If you Log in you could create a "grumbles and groans" node. If you don't already have an account, you can register here.