John and Helen Taylor (shown above) recently began a road trip around the world in an attempt to set a new Guinness World Record for fuel efficiency. The duo plan to cover approximately 18,000 miles, across 25 countries, in 70 days -- all on less than 50 tanks of Shell gasoline specially-formulated using a next- generation fuel technology. Follow the journey online where you can sign up for email progress updates or find out when they're in your neck of the woods (an insider TreeHugger thing). The driving tips the Taylors will be using are given away at Shell stations across the U.S. through the Shell FuelStretch initiative. John and Helen will be driving a Volkswagen Golf FSI 1.6., a version of which is also shown here.