While I'm not a particular fan of hybrids (too "stop gap" in my opinion) this is a way better angle considering diesel's greater fuel efficiency (75% vs. 25% for gas) and the ability to run biodiesel completely negates the use of any petroleum-based fuels:

Coming Soon from VW: A 69.9 MPG Diesel Hybrid
By Chuck Squatriglia February 28, 2008 | 10:04:10 AMCategories: Diesel, Geneva Motor Show, Hybrids

It's official - Volkswagen is unveiling a hybrid to challenge the mighty Toyota Prius. And not just any hybrid, but a diesel-electric hybrid it says will deliver 69.9 mpg.

VW's been experimenting with hybrids of the gasoline-electric variety since the early 1990s, but the Golf hybrid it will unveil next month at the Geneva Motor Show is the first production model the German company's rolled out. Volkswagen isn't offering much in the way of details, but the car is expected to have a parallel hybrid drivetrain with a 2.0 liter engine. Look for it to have an all-electric mode at low speed, start-stop capability, regenerative braking and a 7-speed DSG double-clutch transmission, according to Auto Express and AutoBlog Green.

What's all the techno-jargon mean? The Golf Hybrid will get almost 70 mph while meeting Europe's stringent Euro V and America's Tier 2 Bin 5 emissions standards, making it green enough even for California. The car is said to emit just 89 g/km of CO2. (For comparison, the Prius emits 104 g/km and Honda Civic Hybrid emits 116.)

The hybrid Golf may be just the start.

According to Britain's Channel 4, VW is considering the hybrid drivetrain in a Jetta and Audi A3. DailyTech says it also could appear in the VW Tiguan and Audi Q5 crossover utility vehicles.

Auto Express says the Golf hybrid will be offered for sale in Europe by the end of next year. No word yet on when we might see it on this side of the pond.
What's especially interesting from a historical perspective is that Ferdinand Porsche, the founder of Volkswagen, created the first hybrid car in 1901!