Shell says its V-Power premium gasoline is jam-packed with special additives to keep your engine as clean as the day you bought your vehicle. Those include a nitrogen-enriched cleaning agent designed to lay waste to engine deposits and gunk; fewer deposits mean a more efficient engine and better gas mileage over the long haul. And since V-Power has just earned the top slot as the best-selling premium gasoline in America, the company is giving away a slew of prizes. Gas cards, as you may guess, are up for grabs -- 10 of them, at $250 per. But the grand prize is really a doozy: One year's worth of free V-Power gasoline. As a bonus, Harley-Davidson is also in on the sweepstakes, and everyone who participates in the competition will be simultaneously entered for a chance to win a brand-spanking-new 2010 Harley-Davidson Fat Boy Lo motorcycle worth just shy of $16,300.

If you want in on the action, head here and submit a creative photo with you giving the “V” sign with your car, truck or motorcycle included (like the one above from Tracy S. in Merrick, N.Y.). Then, cook up a 100-word story about how Shell V-Power fuels your passion for your transportation. Shell says contestants can send in poems, songs or love stories to fulfill the story portion, so long as they meet the required length. Sounds easy enough.

You can enter your vehicle in one of five categories: First, the Modified Car category is open to any car that’s been tweaked by the owner. That means any aftermarket performance or cosmetic upgrades, including entertainment additions, are perfect. If your car isn’t a wild ride, the Sports/Luxury Car category might be a better bet. There’s also a Motorcycle portion open to anything with fewer than four wheels, including choppers and bikes of any make or model. If you’ve got a great truck or SUV that thrives on Shell gasoline, the Truck or SUV category will fit you just fine. Finally, an Other Premium Rides category is open to anything that doesn’t quite fit into the other categories. Case in point: A serviceman from Charlotte, N.C., has already entered his International MRAP in that section.