Examples:

• Well, we've got your number, so have a good trip.
• So, did you guys have a good trip up?
• Well, have a good trip back, Colin.
• Now you can have a good trip.
• I hope you have a good trip, too.
• Alright then, have a good trip.
• So I still want to have a good trip.
• Well, Professor, did you have a good trip?