Last week we brought you the Hertz free rental car offer where you receive a free one day car rental - few strings attached. Allegedly you had to pay a few bucks for taxes and fees, but my experience over the weekend resulted in a completely free rental.Now Alamo has upped the ante by offering $10/day car rentals - up to four days in length, through May 31, 2009. Pickup as early as Thursday, return as late as Monday. For example, I just booked a four day rental for Honolulu, Hawaii, with a total cost of $52, compared to the previous $147 I had reserved. Best of all, like the Hertz offer, pre-payment is not required. This offer is valid in most U.S markets and it's good for both airport and in-city rentals.