You guys are doing it wrong
 

Instead of worrying about fuel economy and aerodynamic desinsg you guys should leave well enough alone. Instead work on a "tractor beam" like in star wars so you can beam onto the car ahead of you and let them pull you along. Kind of like drafting. Let him worry about his mpg while you just coast along behind with the engine off

If that idea is to futuristic at least have some telescopic electromagnets that you can attach to the car ahead of you and use high test fishing line to connect

I have entertained the idea of an electromagnet attaching to a big rig for freeway travel. The driver would probably not even notice the extra load on flat ground. It's those pesky laws that I'm really worried about though.

True. Plus the fact that for a lot of us, it's not really our personal fuel consumption that's the fundamental issue, it's the effects of burning petroleum. Thus if I reduce my consumption X amount by causing someone else to increase their consumption by the same amount, I've achieved nothing.

PS: Though drafting a semi should also produce a small aerodynamic benefit for the semi...

For highway travel, it doesn't make sense that thousands of vehicles moving in the same direction and roughly the same speed should individually power themselves. It would be like having an engine attached to each boxcar of a train. Gasoline engines are incredibly inefficient when operating at such low sustained loads.

Attaching your vehicle to a truck and turning the motor off would save a lot of fuel, even when considering the loss of MPGs experienced by the truck.

...big problem with a "train" is that if/when somebody in the middle needs to turn-off for gasoline or potty break, everybody behind him are suddenly gonna be "coasting" much to their surprise!

Vactrain - Wikipedia, the free encyclopedia

Evacuated tube transportation technology.

A ride in a 0 atmosphere tube after being fired by a magnetic rail gun, slowly enough to keep you from disintegrating on your way to 5000 MPH.

regards
Mech

I've always thought it would be quite efficient to send satellites to space using an evacuated tube and rail gun. I just don't know what kind of heat shield would be needed for when the craft exits the tube, or if the sudden impact of hitting 1atm at ~20,000mi/hr would pulverize everything. Build this gun on top of a tall mountain near the equator and you can cut it down to 0.5atm and reduce the required velocity.

Why bother with a tractor beam when you can just make a transporter?

Oh, I don't know... maybe tear around less?

Why bother going anywhere at all? You're already someplace.