A team of 4 men achieve 110 MPG in an unmodified Toyota Prius during a 1400 mile trip. Running for the final 8 hours with the low-fuel light on, they broke the record for sustained mileage over practical distances in a Hybrid.
The Full Story: Post-Gazette
I believe the immediate future is Hybrid though I see a time when we will get off our addiction to fossil fuels permanently for our transportation needs.
If you are wondering what a Prius is and looks like:
View: The Toyota Prius Website
I say in 10 years time I and my wife will both own Hybrid cars.
If you are curious about how "Hybrid Cars" work, check out the following site:
View: How Stuff Works