Findings:

• Sentinel
• Sentinel (user)
• The Sentinel
• sentinel node
• sentinel lymph node biopsy
• The Sentinel (user)
• TIE Sentinel
• sentinel value
• Operation Vigilant Sentinel
• Milwaukee Journal Sentinel
• The inhospitable inhabitants of North Sentinel Island
• Mr. Blocky - Tron Sentinel version
• Dragon Quest IX: Sentinels of the Starry Skies
• North Sentinel Island

If you Log in you could create a "Sentinel of the Spaceways" node. If you don't already have an account, you can register here.