This settings page allows you to specify different cities you are visiting in the future, or that you'd like to visit in the future -- in which case, we'll let you know others from your area that want to go to those cities for carpooling, as well as events that would interest you in that area (or along the way). [Or cities you would go to, period. Because it's a reasonable drive, or because you have friends/relatives there.]

Where are you going in the future?

Where would you like to go in the future?
(city, state, country), optional range of dates (date to date, or up til date -- friend might live there temporarily)

Do you have a car you'd be willing to drive there?

[provide links to airfare, hotels, car rentals]

[allow people participating in the group/event to make a list of things to bring, and people check who is bringing what] [also, people can specify different things they'd like to do/see on the trip]