Like many homeowners, Trotta has been carefully following the slide in crude oil prices with an eye toward locking in a rate at the most opportune time. Trotta’s oil supplier has a page on his Web site that tracks heating oil prices in real time and offers several purchase-plan options.

Despite OPEC's recent decision to cut production, crude oil prices kept tumbling last week, until the Federal Reserve lowered interest rates and that raised expectations of more economic activity and demand for oil. So when Trotta noticed that his vendor’s price had dipped below $3 a gallon, he decided act before the midnight deadline when a new, higher price would presumably go into effect. But he had two ways to go about it:

-- One was to pre-buy an entire winter’s worth of oil at a set price: 1,348 gallons at $2.89 per gallon, for a total of $3,896.

-- Alternatively, he could pre-buy all that oil with a “flexible cap” plan, which meant he would get a lower price if oil prices fell. The problem with the flexible cap plan is that would cost an additional 30 cents per gallon. That added up to an additional $404 on top of the full-season payment. So for Trotta to see any benefit to the flexible plan, oil prices would have to dip to $2.59 a gallon -- prices not seen since the George H.W. Bush administration.

Trotta took the fixed price plan.

Next question: How do you pay for all that oil? Pulling the full amount out of his bank account would cost Trotta about $100 a year in lost interest, but save twice as much in financing fees -- a gain of $100. If he paid with his cash-back American Express card, he would have gotten an additional 1 percent rebate – or roughly $39 in savings. Unfortunately, the oil vendor didn’t take Amex.

Luckily, his wife remembered the new Master Card the couple had just gotten for a furniture purchase. The card offered zero-percent financing, meaning no interest payments until November 2009. So the Trottas ended up buying an entire season’s worth of oil -- and will pay it off month-by-month over the next year without incurring any interest charges.

Trotta plans to invest some of the money he’s saved in making his home more energy efficient -- and the rest in taking his wife out to dinner (smart move, Gian!).

The experts at Consumer Reports have compiled a vast library of advice on how to save money on energy around the house, much of which is free.

Meanwhile, we’d like to hear how you’re coping with this season’s high-heating costs. Are you turning down the thermostat, wearing extra layers, adding insulation, or stuffing towels under the door to keep out cold air? Post a comment to this blog, or write to me at tightwad at cro dot consumer dot org.