Sometimes you need a car, so here's my resolution: I will be as diligent hunting for a car as I am for airfare. If you're locked into your dates, you can name your own price on Priceline, which will make you pay upfront and probably won't refund if you have to cancel. That's not always the best answer, though. Check individual car rental companies (for a list, go to the L.A. Times Travel Vacation Planning page or try Rentalcars.com, which is affiliated with Priceline. I recently tried a random four-day rental for Philadelphia in mid-January and found a Hyundai Accent through RentalCars.com for $27.74 a day at Payless and the same car for $20 a day at Rent-a-Wreck. Using the aggregator site Kayak.com, I found a Ford Focus for $32 a day at Budget. But then I tried a trick I often use when shopping online and Googled "promo code" and, randomly, "Enterprise." Up popped a $9.99-a-day weekend special for Enterprise. It said only that it was a compact car, and the deal wasn't available everywhere, but it was the best deal I found.