Findings:

• the obligatory love subplot
• tipper (user)
• tipper lorry
• Big Tippers
• Bad tippers in restaurants
• Tipper Gore
• tipper
• Obligatory hospital wing chapter
• obligatory
• Medium Obligatory Prayer
• Short Obligatory Prayer
• Long Obligatory Prayer
• The obligatory CowboyNeal option on every Slashdot poll
• Obligatory Nonsensical Answer
• obligatory fighting-game bimbo
• Obligatory Cute Anime Animal
• Obligatory Roommate Dream

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