Road Trip - Planning

As reported earlier, airfare is on the rise.  You still need to take a vacation, so why not road trip.

Use GasBuddy and this really cool road trip planner, Mile by Mile. 

Road Trip advice, from RoadTrip America is also a good resource. 

If you are traveling with a diverse group:

Don't commit to a trip until you are sure you are going. Be sure you can get/have the time off work, have enough money, etc. If your plans change after a carpool has been put together, let people know right away.
You should not take a trip solely because someone else wants you to.  The drive to your vacation can ruin the vacation.

You should not accept people in your carpool that you do not trust or you know you do not like just because someone else can't live without them.  Do your packing well before your pickup time or time to meet at a designated place.  There is no excuse for passengers who don't bring money and/or a credit card for their share of gas, park entrance fees, toll fees, chain rentals, etc. Driving chores do not have to be shared evenly, but gas costs etc. do.

You will probably leave town later than you think because it will take longer to pack up than you think, especially with a big group. This means you might arrive after dark even if you were certain you would not. Have your flashlight, jacket where you can get to them, not packed away.

Decisions to make BEFORE the trip:
Decide on the full trip length in advance, and not just as you are starting out. If someone needs to be back at work, or ... by a deadline then people need to agree to that return time or not travel together.
Decide in advance if you will drive straight through or make many stops at specific sightseeing places or unspecific we've-got-to-see-that routes suggested by billboards.

Be sure you are all in agreement about short or long stops. Sometimes this can be up to the driver, sometimes it's a group decision. The drive from the SF Bay area to Yosemite, for example, can take 4 plus hours if you don't make many stops, aren't behind slow drivers and do the speed limit. Or it can take 5-6 or more hours if you have a lot of passengers who want fast food or photo taking stops, or you have to put on chains and drive slowly.

On a longer cross country or regional road trip, if you have a destination with a certain time, at least plan for some stops. Maybe each person can have one half-hour spontaneous we've-got-to-check-this-out event.

Be sure you agree on food spending as well. If some of the carpool are on a budget, they probably want to eat the food they packed, or fast food, not stop for sit-down restaurant meals. Those who are feeling rich can get fast food on the drive and save their expensive meals for at the destination itself.
Other people in the vehicle will appreciate it if you wear freshly laundered clothing without perfume or cologne and have recently washed yourself and brushed your teeth.

Everyone in the vehicle should agree as to the music being played or they should plan to bring headphone players. Some groups say the driver gets to decide. Some say that others have some veto power.