Oil rose above $68 a barrel on Tuesday, reversing earlier losses, supported by a weaker dollar and ahead of inventory data expected to show a fall in crude stocks.

Here at Money Morning over the past six months, we’ve talked a great deal about oil and gasoline prices. We’ve offered our predictions about how high those prices were going, and have detailed a number of investment opportunities – chosen as much for their margins of safety as for their profit potential.

Rail has a powerful tenfold advantage over trucking when fuel costs are high. Heavy Trucks require 3,357 BTU per short ton mile while Class 1 Railroads use only 341 BTU per short ton mile.

As high prices at the pumps and the rise of biofuels cut into demand for gasoline, US oil refiners are switching their attention to diesel.

“The trend that is important behind the story of the future expansions is the downtrend in gasoline,” said Joanne Shore, analyst for the U.S. Energy Information Administration, speaking to Thomson Reuters.

“We feel that demand for distillates is going to be higher than gasoline for the next several years.

Just imagine if gasoline cost $20 a gallon. You’d start by cutting your driving in half. Then you’d almost never go out to restaurants, because food would become so expensive. You’d probably pull the old bike out of the closet. America would scream bloody murder and lynch the CEO of ExxonMobil.

US truckers have started an ad hoc protest across the country over recent hikes in fuel prices, reports AP.

Some truckers, on CB radios and trucking Web sites, had called for a strike Tuesday to protest the high cost of diesel fuel, saying the action might pressure President Bush to stabilize prices by using the nation’s oil reserves. But the protests were scattered because because major trucking companies were not on board and there did not appear to be any central coordination.